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• Confirm disk is broken when it passes all diagnostics

  - by Halfgaar

  I have a system with a potentially broken disk, but the disk passes all manner of diagnostics. I have been unable to confirm that the disk is broken. What are my options? I could just replace the disk, but because this situation is very similar to another more severe situation I have (long story), I'd like to actually make a proper diagnosis as opposed to randomly binning hardware. The issue and history is this: I had a Debian Linux PC (500 MHz P3) acting as router, nagios and munin. It crashed every couple of weeks. No logs or dmesg could be obtained (because it's an old Compaq that only boots when you configure it as keyboardless, making connecting a keyboard later, once it's booted, impossible). At the time, I just replaced the computer with another Compaq (P4 2.4 GHz) because I thought the hardware was faulty. However, it still crashed every couple of weeks. the difference is that on this computer, I can still SSH into it. It gives all kinds of errors on hda. I'd like to confirm that the disk is broken, but nothing I do confirms this: SMART error logs shows no errors. Normally when a disk starts acting up, SMART my pass, but it still records a read-error in the error log. SMART self-test (smartctl -t long /dev/sda) completes without errors. re-allocated sector count (a tell-tale parameter) has been 31 all its life, even when the disk was still in use in my desktop PC years ago, and it still is. The figure never changed. dd if=/dev/sda of=/dev/null bs=4096 passes with flying colors. What else can I do to assess the health of the drive? Again, this is not about making this router fully functional again, this is a disk forensic question, because it just so happens that I have another server that potentially has the same problem, and knowing the answer to this will possibly help me greatly. For the record, below are logs and such. This is the smartctl -a output: smartctl 5.40 2010-07-12 r3124 [i686-pc-linux-gnu] (local build) Copyright (C) 2002-10 by Bruce Allen, http://smartmontools.sourceforge.net === START OF INFORMATION SECTION === Model Family: Seagate Barracuda 7200.7 and 7200.7 Plus family Device Model: ST3120026A Serial Number: 5JT1CLQM Firmware Version: 3.06 User Capacity: 120,034,123,776 bytes Device is: In smartctl database [for details use: -P show] ATA Version is: 6 ATA Standard is: ATA/ATAPI-6 T13 1410D revision 2 Local Time is: Mon Jul 1 21:18:33 2013 CEST SMART support is: Available - device has SMART capability. SMART support is: Enabled === START OF READ SMART DATA SECTION === SMART overall-health self-assessment test result: PASSED General SMART Values: Offline data collection status: (0x82) Offline data collection activity was completed without error. Auto Offline Data Collection: Enabled. Self-test execution status: ( 24) The self-test routine was aborted by the host. Total time to complete Offline data collection: ( 430) seconds. Offline data collection capabilities: (0x5b) SMART execute Offline immediate. Auto Offline data collection on/off support. Suspend Offline collection upon new command. Offline surface scan supported. Self-test supported. No Conveyance Self-test supported. Selective Self-test supported. SMART capabilities: (0x0003) Saves SMART data before entering power-saving mode. Supports SMART auto save timer. Error logging capability: (0x01) Error logging supported. No General Purpose Logging support. Short self-test routine recommended polling time: ( 1) minutes. Extended self-test routine recommended polling time: ( 85) minutes. SMART Attributes Data Structure revision number: 10 Vendor Specific SMART Attributes with Thresholds: ID# ATTRIBUTE_NAME FLAG VALUE WORST THRESH TYPE UPDATED WHEN_FAILED RAW_VALUE 1 Raw_Read_Error_Rate 0x000f 050 046 006 Pre-fail Always - 47766662 3 Spin_Up_Time 0x0003 097 096 000 Pre-fail Always - 0 4 Start_Stop_Count 0x0032 100 100 020 Old_age Always - 10 5 Reallocated_Sector_Ct 0x0033 100 100 036 Pre-fail Always - 31 7 Seek_Error_Rate 0x000f 084 060 030 Pre-fail Always - 820305 9 Power_On_Hours 0x0032 048 048 000 Old_age Always - 46373 10 Spin_Retry_Count 0x0013 100 100 097 Pre-fail Always - 0 12 Power_Cycle_Count 0x0032 100 100 020 Old_age Always - 605 194 Temperature_Celsius 0x0022 036 065 000 Old_age Always - 36 195 Hardware_ECC_Recovered 0x001a 050 046 000 Old_age Always - 47766662 197 Current_Pending_Sector 0x0012 100 100 000 Old_age Always - 0 198 Offline_Uncorrectable 0x0010 100 100 000 Old_age Offline - 0 199 UDMA_CRC_Error_Count 0x003e 200 196 000 Old_age Always - 6 200 Multi_Zone_Error_Rate 0x0000 100 253 000 Old_age Offline - 0 202 Data_Address_Mark_Errs 0x0032 100 253 000 Old_age Always - 0 SMART Error Log Version: 1 No Errors Logged SMART Self-test log structure revision number 1 Num Test_Description Status Remaining LifeTime(hours) LBA_of_first_error # 1 Extended offline Aborted by host 80% 46361 - # 2 Extended offline Completed without error 00% 46358 - # 3 Short offline Completed without error 00% 12046 - # 4 Extended offline Completed without error 00% 10472 - # 5 Short offline Completed without error 00% 10471 - # 6 Short offline Completed without error 00% 10471 - # 7 Short offline Completed without error 00% 6770 - # 8 Extended offline Aborted by host 90% 5958 - # 9 Extended offline Aborted by host 90% 5951 - #10 Short offline Completed without error 00% 5024 - #11 Extended offline Aborted by host 80% 5024 - #12 Short offline Completed without error 00% 3697 - #13 Short offline Completed without error 00% 237 - #14 Short offline Completed without error 00% 145 - #15 Short offline Completed without error 00% 69 - #16 Extended offline Completed without error 00% 68 - #17 Short offline Completed without error 00% 66 - #18 Short offline Completed without error 00% 49 - #19 Short offline Completed without error 00% 29 - #20 Short offline Completed without error 00% 29 - SMART Selective self-test log data structure revision number 1 SPAN MIN_LBA MAX_LBA CURRENT_TEST_STATUS 1 0 0 Not_testing 2 0 0 Not_testing 3 0 0 Not_testing 4 0 0 Not_testing 5 0 0 Not_testing Selective self-test flags (0x0): After scanning selected spans, do NOT read-scan remainder of disk. If Selective self-test is pending on power-up, resume after 0 minute delay. And this is the dmesg error when it has crashed (which repeats for a bunch of different sectors): [1755091.211136] sd 0:0:0:0: [sda] Unhandled error code [1755091.211144] sd 0:0:0:0: [sda] Result: hostbyte=DID_BAD_TARGET driverbyte=DRIVER_OK [1755091.211151] sd 0:0:0:0: [sda] CDB: Read(10): 28 00 08 fe ad 38 00 00 08 00 [1755091.211166] end_request: I/O error, dev sda, sector 150908216

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• Optimizing MySQL for small VPS

  - by Chris M

  I'm trying to optimize my MySQL config for a verrry small VPS. The VPS is also running NGINX/PHP-FPM and Magento; all with a limit of 250MB of RAM. This is an output of MySQL Tuner... -------- General Statistics -------------------------------------------------- [--] Skipped version check for MySQLTuner script [OK] Currently running supported MySQL version 5.1.41-3ubuntu12.8 [OK] Operating on 64-bit architecture -------- Storage Engine Statistics ------------------------------------------- [--] Status: -Archive -BDB -Federated +InnoDB -ISAM -NDBCluster [--] Data in MyISAM tables: 1M (Tables: 14) [--] Data in InnoDB tables: 29M (Tables: 301) [--] Data in MEMORY tables: 1M (Tables: 17) [!!] Total fragmented tables: 301 -------- Security Recommendations ------------------------------------------- [OK] All database users have passwords assigned -------- Performance Metrics ------------------------------------------------- [--] Up for: 2d 11h 14m 58s (1M q [8.038 qps], 33K conn, TX: 2B, RX: 618M) [--] Reads / Writes: 83% / 17% [--] Total buffers: 122.0M global + 8.6M per thread (100 max threads) [!!] Maximum possible memory usage: 978.2M (404% of installed RAM) [OK] Slow queries: 0% (37/1M) [OK] Highest usage of available connections: 6% (6/100) [OK] Key buffer size / total MyISAM indexes: 32.0M/282.0K [OK] Key buffer hit rate: 99.7% (358K cached / 1K reads) [OK] Query cache efficiency: 83.4% (1M cached / 1M selects) [!!] Query cache prunes per day: 48301 [OK] Sorts requiring temporary tables: 0% (0 temp sorts / 144K sorts) [OK] Temporary tables created on disk: 13% (27K on disk / 203K total) [OK] Thread cache hit rate: 99% (6 created / 33K connections) [!!] Table cache hit rate: 0% (32 open / 51K opened) [OK] Open file limit used: 1% (20/1K) [OK] Table locks acquired immediately: 99% (1M immediate / 1M locks) [!!] InnoDB data size / buffer pool: 29.2M/8.0M -------- Recommendations ----------------------------------------------------- General recommendations: Run OPTIMIZE TABLE to defragment tables for better performance Reduce your overall MySQL memory footprint for system stability Enable the slow query log to troubleshoot bad queries Increase table_cache gradually to avoid file descriptor limits Variables to adjust: *** MySQL's maximum memory usage is dangerously high *** *** Add RAM before increasing MySQL buffer variables *** query_cache_size (> 64M) table_cache (> 32) innodb_buffer_pool_size (>= 29M) and this is the config. # # The MySQL database server configuration file. # # You can copy this to one of: # - "/etc/mysql/my.cnf" to set global options, # - "~/.my.cnf" to set user-specific options. # # One can use all long options that the program supports. # Run program with --help to get a list of available options and with # --print-defaults to see which it would actually understand and use. # # For explanations see # http://dev.mysql.com/doc/mysql/en/server-system-variables.html # This will be passed to all mysql clients # It has been reported that passwords should be enclosed with ticks/quotes # escpecially if they contain "#" chars... # Remember to edit /etc/mysql/debian.cnf when changing the socket location. [client] port = 3306 socket = /var/run/mysqld/mysqld.sock # Here is entries for some specific programs # The following values assume you have at least 32M ram # This was formally known as [safe_mysqld]. Both versions are currently parsed. [mysqld_safe] socket = /var/run/mysqld/mysqld.sock nice = 0 [mysqld] # # * Basic Settings # # # * IMPORTANT # If you make changes to these settings and your system uses apparmor, you may # also need to also adjust /etc/apparmor.d/usr.sbin.mysqld. # user = mysql socket = /var/run/mysqld/mysqld.sock port = 3306 basedir = /usr datadir = /var/lib/mysql tmpdir = /tmp skip-external-locking # # Instead of skip-networking the default is now to listen only on # localhost which is more compatible and is not less secure. bind-address = 127.0.0.1 # # * Fine Tuning # key_buffer = 32M max_allowed_packet = 16M thread_stack = 192K thread_cache_size = 8 sort_buffer_size = 4M read_buffer_size = 4M myisam_sort_buffer_size = 16M # This replaces the startup script and checks MyISAM tables if needed # the first time they are touched myisam-recover = BACKUP max_connections = 100 table_cache = 32 tmp_table_size = 128M #thread_concurrency = 10 # # * Query Cache Configuration # #query_cache_limit = 1M query_cache_type = 1 query_cache_size = 64M # # * Logging and Replication # # Both location gets rotated by the cronjob. # Be aware that this log type is a performance killer. # As of 5.1 you can enable the log at runtime! #general_log_file = /var/log/mysql/mysql.log #general_log = 1 log_error = /var/log/mysql/error.log # Here you can see queries with especially long duration #log_slow_queries = /var/log/mysql/mysql-slow.log #long_query_time = 2 #log-queries-not-using-indexes # # The following can be used as easy to replay backup logs or for replication. # note: if you are setting up a replication slave, see README.Debian about # other settings you may need to change. #server-id = 1 #log_bin = /var/log/mysql/mysql-bin.log expire_logs_days = 10 max_binlog_size = 100M #binlog_do_db = include_database_name #binlog_ignore_db = include_database_name # # * InnoDB # # InnoDB is enabled by default with a 10MB datafile in /var/lib/mysql/. # Read the manual for more InnoDB related options. There are many! # # * Security Features # # Read the manual, too, if you want chroot! # chroot = /var/lib/mysql/ # # For generating SSL certificates I recommend the OpenSSL GUI "tinyca". # # ssl-ca=/etc/mysql/cacert.pem # ssl-cert=/etc/mysql/server-cert.pem # ssl-key=/etc/mysql/server-key.pem [mysqldump] quick quote-names max_allowed_packet = 16M [mysql] #no-auto-rehash # faster start of mysql but no tab completition [isamchk] key_buffer = 16M # # * IMPORTANT: Additional settings that can override those from this file! # The files must end with '.cnf', otherwise they'll be ignored. # !includedir /etc/mysql/conf.d/ The site contains 1 wordpress site,so lots of MYISAM but mostly static content as its not changing all that often (A wordpress cache plugin deals with this). And the Magento Site which consists of a lot of InnoDB tables, some MyISAM and some INMEMORY. The "read" side seems to be running pretty well with a mass of optimizations I've used on Magento, the NGINX setup and PHP-FPM + XCACHE. I'd love to have a kick in the right direction with the MySQL config so I'm not blindly altering it based on the MySQLTuner without understanding what I'm changing. Thanks

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• Server Memory with Magento

  - by Mohamed Elgharabawy

  I have a cloud server with the following specifications: 2vCPUs 4G RAM 160GB Disk Space Network 400Mb/s System Image: Ubuntu 12.04 LTS I am only running Magento CE 1.7.0.2 on this server. Nothing else. Usually, the server has a loading time of 4-5 seconds. Recently, this has dropped to over 30 seconds and sometimes the server just goes away and I get HTTP error reports to my email stating that HTTP requests took more than 20000ms. Running top command and sorting them returns the following: top - 15:29:07 up 3:40, 1 user, load average: 28.59, 25.95, 22.91 Tasks: 112 total, 30 running, 82 sleeping, 0 stopped, 0 zombie Cpu(s): 90.2%us, 9.3%sy, 0.0%ni, 0.0%id, 0.0%wa, 0.0%hi, 0.3%si, 0.2%st PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND 31901 www-data 20 0 360m 71m 5840 R 7 1.8 1:39.51 apache2 32084 www-data 20 0 362m 72m 5548 R 7 1.8 1:31.56 apache2 32089 www-data 20 0 348m 59m 5660 R 7 1.5 1:41.74 apache2 32295 www-data 20 0 343m 54m 5532 R 7 1.4 2:00.78 apache2 32303 www-data 20 0 354m 65m 5260 R 7 1.6 1:38.76 apache2 32304 www-data 20 0 346m 56m 5544 R 7 1.4 1:41.26 apache2 32305 www-data 20 0 348m 59m 5640 R 7 1.5 1:50.11 apache2 32291 www-data 20 0 358m 69m 5256 R 6 1.7 1:44.26 apache2 32517 www-data 20 0 345m 56m 5532 R 6 1.4 1:45.56 apache2 30473 www-data 20 0 355m 66m 5680 R 6 1.7 2:00.05 apache2 32093 www-data 20 0 352m 63m 5848 R 6 1.6 1:53.23 apache2 32302 www-data 20 0 345m 56m 5512 R 6 1.4 1:55.87 apache2 32433 www-data 20 0 346m 57m 5500 S 6 1.4 1:31.58 apache2 32638 www-data 20 0 354m 65m 5508 R 6 1.6 1:36.59 apache2 32230 www-data 20 0 347m 57m 5524 R 6 1.4 1:33.96 apache2 32231 www-data 20 0 355m 66m 5512 R 6 1.7 1:37.47 apache2 32233 www-data 20 0 354m 64m 6032 R 6 1.6 1:59.74 apache2 32300 www-data 20 0 355m 66m 5672 R 6 1.7 1:43.76 apache2 32510 www-data 20 0 347m 58m 5512 R 6 1.5 1:42.54 apache2 32521 www-data 20 0 348m 59m 5508 R 6 1.5 1:47.99 apache2 32639 www-data 20 0 344m 55m 5512 R 6 1.4 1:34.25 apache2 32083 www-data 20 0 345m 56m 5696 R 5 1.4 1:59.42 apache2 32085 www-data 20 0 347m 58m 5692 R 5 1.5 1:42.29 apache2 32293 www-data 20 0 353m 64m 5676 R 5 1.6 1:52.73 apache2 32301 www-data 20 0 348m 59m 5564 R 5 1.5 1:49.63 apache2 32528 www-data 20 0 351m 62m 5520 R 5 1.6 1:36.11 apache2 31523 mysql 20 0 3460m 576m 8288 S 5 14.4 2:06.91 mysqld 32002 www-data 20 0 345m 55m 5512 R 5 1.4 2:01.88 apache2 32080 www-data 20 0 357m 68m 5512 S 5 1.7 1:31.30 apache2 32163 www-data 20 0 347m 58m 5512 S 5 1.5 1:58.68 apache2 32509 www-data 20 0 345m 56m 5504 R 5 1.4 1:49.54 apache2 32306 www-data 20 0 358m 68m 5504 S 4 1.7 1:53.29 apache2 32165 www-data 20 0 344m 55m 5524 S 4 1.4 1:40.71 apache2 32640 www-data 20 0 345m 56m 5528 R 4 1.4 1:36.49 apache2 31888 www-data 20 0 359m 70m 5664 R 4 1.8 1:57.07 apache2 32511 www-data 20 0 357m 67m 5512 S 3 1.7 1:47.00 apache2 32054 www-data 20 0 357m 68m 5660 S 2 1.7 1:53.10 apache2 1 root 20 0 24452 2276 1232 S 0 0.1 0:01.58 init Moreover, running free -m returns the following: total used free shared buffers cached Mem: 4003 3919 83 0 118 901 -/+ buffers/cache: 2899 1103 Swap: 0 0 0 To investigate this further, I have installed apache buddy, it recommeneded that I need to reduce the maxclient connections. Which I did. I also installed MysqlTuner and it suggests that I need to set my innodb_buffer_pool_size to = 3.0G. However, I cannot do that, since the whole memory is 4G. Here is the output from apache buddy: ### GENERAL REPORT ### Settings considered for this report: Your server's physical RAM: 4003MB Apache's MaxClients directive: 40 Apache MPM Model: prefork Largest Apache process (by memory): 73.77MB [ OK ] Your MaxClients setting is within an acceptable range. Max potential memory usage: 2950.8 MB Percentage of RAM allocated to Apache 73.72 % And this is the output of MySQLTuner: -------- Performance Metrics ------------------------------------------------- [--] Up for: 47m 22s (675K q [237.552 qps], 12K conn, TX: 1B, RX: 300M) [--] Reads / Writes: 45% / 55% [--] Total buffers: 2.1G global + 2.7M per thread (151 max threads) [OK] Maximum possible memory usage: 2.5G (64% of installed RAM) [OK] Slow queries: 0% (0/675K) [OK] Highest usage of available connections: 26% (40/151) [OK] Key buffer size / total MyISAM indexes: 36.0M/18.7M [OK] Key buffer hit rate: 100.0% (245K cached / 105 reads) [OK] Query cache efficiency: 92.5% (500K cached / 541K selects) [!!] Query cache prunes per day: 302886 [OK] Sorts requiring temporary tables: 0% (1 temp sorts / 15K sorts) [!!] Joins performed without indexes: 12135 [OK] Temporary tables created on disk: 25% (8K on disk / 32K total) [OK] Thread cache hit rate: 90% (1K created / 12K connections) [!!] Table cache hit rate: 17% (400 open / 2K opened) [OK] Open file limit used: 12% (123/1K) [OK] Table locks acquired immediately: 100% (196K immediate / 196K locks) [!!] InnoDB buffer pool / data size: 2.0G/3.5G [OK] InnoDB log waits: 0 -------- Recommendations ----------------------------------------------------- General recommendations: Run OPTIMIZE TABLE to defragment tables for better performance MySQL started within last 24 hours - recommendations may be inaccurate Enable the slow query log to troubleshoot bad queries Adjust your join queries to always utilize indexes Increase table_cache gradually to avoid file descriptor limits Read this before increasing table_cache over 64: http://bit.ly/1mi7c4C Variables to adjust: query_cache_size ( 64M) join_buffer_size ( 128.0K, or always use indexes with joins) table_cache ( 400) innodb_buffer_pool_size (= 3G) Last but not least, the server still has more than 60% of free disk space. Now, based on the above, I have few questions: Are these numbers normal? Do they make sense? Do I need to upgrade the server? If I don't need to upgrade and my configuration is not correct, how do I optimize it?

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• jQuery Validate - require at least one field in a group to be filled

  - by Nathan Long

  I'm using the excellent jQuery Validate Plugin to validate some forms. On one form, I need to ensure that the user fills in at least one of a group of fields. I think I've got a pretty good solution, and wanted to share it. Please suggest any improvements you can think of. Finding no built-in way to do this, I searched and found Rebecca Murphey's custom validation method, which was very helpful. I improved this in three ways: To let you pass in a selector for the group of fields To let you specify how many of that group must be filled for validation to pass To show all inputs in the group as passing validation as soon as one of them passes validation. So you can say "at least X inputs that match selector Y must be filled." The end result is a rule like this: partnumber: { require_from_group: [2,".productinfo"] } //The partnumber input will validate if //at least 2 `.productinfo` inputs are filled For best results, put this rule AFTER any formatting rules for that field (like "must contain only numbers", etc). This way, if the user gets an error from this rule and starts filling out one of the fields, they will get immediate feedback about the formatting required without having to fill another field first. Item #3 assumes that you're adding a class of .checked to your error messages upon successful validation. You can do this as follows, as demonstrated here. success: function(label) { label.html(" ").addClass("checked"); } As in the demo linked above, I use CSS to give each span.error an X image as its background, unless it has the class .checked, in which case it gets a check mark image. Here's my code so far: jQuery.validator.addMethod("require_from_group", function(value, element, options) { // From the options array, find out what selector matches // our group of inputs and how many of them should be filled. numberRequired = options[0]; selector = options[1]; var commonParent = $(element).parents('form'); var numberFilled = 0; commonParent.find(selector).each(function(){ // Look through fields matching our selector and total up // how many of them have been filled if ($(this).val()) { numberFilled++; } }); if (numberFilled >= numberRequired) { // This part is a bit of a hack - we make these // fields look like they've passed validation by // hiding their error messages, etc. Strictly speaking, // they haven't been re-validated, though, so it's possible // that we're hiding another validation problem. But there's // no way (that I know of) to trigger actual re-validation, // and in any case, any other errors will pop back up when // the user tries to submit the form. // If anyone knows a way to re-validate, please comment. // // For imputs matching our selector, remove error class // from their text. commonParent.find(selector).removeClass('error'); // Also look for inserted error messages and mark them // with class 'checked' var remainingErrors = commonParent.find(selector) .next('label.error').not('.checked'); remainingErrors.text("").addClass('checked'); // Tell the Validate plugin that this test passed return true; } // The {0} in the next line is the 0th item in the options array }, jQuery.format("Please fill out at least {0} of these fields.")); Questions? Comments?

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• Parallelism in .NET – Part 3, Imperative Data Parallelism: Early Termination

  - by Reed

  Although simple data parallelism allows us to easily parallelize many of our iteration statements, there are cases that it does not handle well.  In my previous discussion, I focused on data parallelism with no shared state, and where every element is being processed exactly the same. Unfortunately, there are many common cases where this does not happen.  If we are dealing with a loop that requires early termination, extra care is required when parallelizing. Often, while processing in a loop, once a certain condition is met, it is no longer necessary to continue processing.  This may be a matter of finding a specific element within the collection, or reaching some error case.  The important distinction here is that, it is often impossible to know until runtime, what set of elements needs to be processed. In my initial discussion of data parallelism, I mentioned that this technique is a candidate when you can decompose the problem based on the data involved, and you wish to apply a single operation concurrently on all of the elements of a collection.  This covers many of the potential cases, but sometimes, after processing some of the elements, we need to stop processing. As an example, lets go back to our previous Parallel.ForEach example with contacting a customer.  However, this time, we’ll change the requirements slightly.  In this case, we’ll add an extra condition – if the store is unable to email the customer, we will exit gracefully.  The thinking here, of course, is that if the store is currently unable to email, the next time this operation runs, it will handle the same situation, so we can just skip our processing entirely.  The original, serial case, with this extra condition, might look something like the following: foreach(var customer in customers) { // Run some process that takes some time... DateTime lastContact = theStore.GetLastContact(customer); TimeSpan timeSinceContact = DateTime.Now - lastContact; // If it's been more than two weeks, send an email, and update... if (timeSinceContact.Days > 14) { // Exit gracefully if we fail to email, since this // entire process can be repeated later without issue. if (theStore.EmailCustomer(customer) == false) break; customer.LastEmailContact = DateTime.Now; } } .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; } Here, we’re processing our loop, but at any point, if we fail to send our email successfully, we just abandon this process, and assume that it will get handled correctly the next time our routine is run.  If we try to parallelize this using Parallel.ForEach, as we did previously, we’ll run into an error almost immediately: the break statement we’re using is only valid when enclosed within an iteration statement, such as foreach.  When we switch to Parallel.ForEach, we’re no longer within an iteration statement – we’re a delegate running in a method. This needs to be handled slightly differently when parallelized.  Instead of using the break statement, we need to utilize a new class in the Task Parallel Library: ParallelLoopState.  The ParallelLoopState class is intended to allow concurrently running loop bodies a way to interact with each other, and provides us with a way to break out of a loop.  In order to use this, we will use a different overload of Parallel.ForEach which takes an IEnumerable<T> and an Action<T, ParallelLoopState> instead of an Action<T>.  Using this, we can parallelize the above operation by doing: Parallel.ForEach(customers, (customer, parallelLoopState) => { // Run some process that takes some time... DateTime lastContact = theStore.GetLastContact(customer); TimeSpan timeSinceContact = DateTime.Now - lastContact; // If it's been more than two weeks, send an email, and update... if (timeSinceContact.Days > 14) { // Exit gracefully if we fail to email, since this // entire process can be repeated later without issue. if (theStore.EmailCustomer(customer) == false) parallelLoopState.Break(); else customer.LastEmailContact = DateTime.Now; } }); There are a couple of important points here.  First, we didn’t actually instantiate the ParallelLoopState instance.  It was provided directly to us via the Parallel class.  All we needed to do was change our lambda expression to reflect that we want to use the loop state, and the Parallel class creates an instance for our use.  We also needed to change our logic slightly when we call Break().  Since Break() doesn’t stop the program flow within our block, we needed to add an else case to only set the property in customer when we succeeded.  This same technique can be used to break out of a Parallel.For loop. That being said, there is a huge difference between using ParallelLoopState to cause early termination and to use break in a standard iteration statement.  When dealing with a loop serially, break will immediately terminate the processing within the closest enclosing loop statement.  Calling ParallelLoopState.Break(), however, has a very different behavior. The issue is that, now, we’re no longer processing one element at a time.  If we break in one of our threads, there are other threads that will likely still be executing.  This leads to an important observation about termination of parallel code: Early termination in parallel routines is not immediate.  Code will continue to run after you request a termination. This may seem problematic at first, but it is something you just need to keep in mind while designing your routine.  ParallelLoopState.Break() should be thought of as a request.  We are telling the runtime that no elements that were in the collection past the element we’re currently processing need to be processed, and leaving it up to the runtime to decide how to handle this as gracefully as possible.  Although this may seem problematic at first, it is a good thing.  If the runtime tried to immediately stop processing, many of our elements would be partially processed.  It would be like putting a return statement in a random location throughout our loop body – which could have horrific consequences to our code’s maintainability. In order to understand and effectively write parallel routines, we, as developers, need a subtle, but profound shift in our thinking.  We can no longer think in terms of sequential processes, but rather need to think in terms of requests to the system that may be handled differently than we’d first expect.  This is more natural to developers who have dealt with asynchronous models previously, but is an important distinction when moving to concurrent programming models. As an example, I’ll discuss the Break() method.  ParallelLoopState.Break() functions in a way that may be unexpected at first.  When you call Break() from a loop body, the runtime will continue to process all elements of the collection that were found prior to the element that was being processed when the Break() method was called.  This is done to keep the behavior of the Break() method as close to the behavior of the break statement as possible. We can see the behavior in this simple code: var collection = Enumerable.Range(0, 20); var pResult = Parallel.ForEach(collection, (element, state) => { if (element > 10) { Console.WriteLine("Breaking on {0}", element); state.Break(); } Console.WriteLine(element); }); If we run this, we get a result that may seem unexpected at first: 0 2 1 5 6 3 4 10 Breaking on 11 11 Breaking on 12 12 9 Breaking on 13 13 7 8 Breaking on 15 15 What is occurring here is that we loop until we find the first element where the element is greater than 10.  In this case, this was found, the first time, when one of our threads reached element 11.  It requested that the loop stop by calling Break() at this point.  However, the loop continued processing until all of the elements less than 11 were completed, then terminated.  This means that it will guarantee that elements 9, 7, and 8 are completed before it stops processing.  You can see our other threads that were running each tried to break as well, but since Break() was called on the element with a value of 11, it decides which elements (0-10) must be processed. If this behavior is not desirable, there is another option.  Instead of calling ParallelLoopState.Break(), you can call ParallelLoopState.Stop().  The Stop() method requests that the runtime terminate as soon as possible , without guaranteeing that any other elements are processed.  Stop() will not stop the processing within an element, so elements already being processed will continue to be processed.  It will prevent new elements, even ones found earlier in the collection, from being processed.  Also, when Stop() is called, the ParallelLoopState’s IsStopped property will return true.  This lets longer running processes poll for this value, and return after performing any necessary cleanup. The basic rule of thumb for choosing between Break() and Stop() is the following. Use ParallelLoopState.Stop() when possible, since it terminates more quickly.  This is particularly useful in situations where you are searching for an element or a condition in the collection.  Once you’ve found it, you do not need to do any other processing, so Stop() is more appropriate. Use ParallelLoopState.Break() if you need to more closely match the behavior of the C# break statement. Both methods behave differently than our C# break statement.  Unfortunately, when parallelizing a routine, more thought and care needs to be put into every aspect of your routine than you may otherwise expect.  This is due to my second observation: Parallelizing a routine will almost always change its behavior. This sounds crazy at first, but it’s a concept that’s so simple its easy to forget.  We’re purposely telling the system to process more than one thing at the same time, which means that the sequence in which things get processed is no longer deterministic.  It is easy to change the behavior of your routine in very subtle ways by introducing parallelism.  Often, the changes are not avoidable, even if they don’t have any adverse side effects.  This leads to my final observation for this post: Parallelization is something that should be handled with care and forethought, added by design, and not just introduced casually.

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• SQL Server and Hyper-V Dynamic Memory - Part 1

  - by SQLOS Team

  SQL and Dynamic Memory Blog Post Series   Hyper-V Dynamic Memory is a new feature in Windows Server 2008 R2 SP1 that allows the memory assigned to guest virtual machines to vary according to demand. Using this feature with SQL Server is supported, but how well does it work in an environment where available memory can vary dynamically, especially since SQL Server likes memory, and is not very eager to let go of it? The next three posts will look at this question in detail. In Part 1 Serdar Sutay, a program manager in the Windows Hyper-V team, introduces Dynamic Memory with an overview of the basic architecture, configuration and monitoring concepts. In subsequent parts we will look at SQL Server memory handling, and develop some guidelines on using SQL Server with Dynamic Memory.   Part 1: Dynamic Memory Introduction   In virtualized environments memory is often the bottleneck for reaching higher VM densities. In Windows Server 2008 R2 SP1 Hyper-V introduced a new feature “Dynamic Memory” to improve VM densities on Hyper-V hosts. Dynamic Memory increases the memory utilization in virtualized environments by enabling VM memory to be changed dynamically when the VM is running.   This brings up the question of how to utilize this feature with SQL Server VMs as SQL Server performance is very sensitive to the memory being used. In the next three posts we’ll discuss the internals of Dynamic Memory, SQL Server Memory Management and how to use Dynamic Memory with SQL Server VMs.   Memory Utilization Efficiency in Virtualized Environments   The primary reason memory is usually the bottleneck for higher VM densities is that users tend to be generous when assigning memory to their VMs. Here are some memory sizing practices we’ve heard from customers:   ·         I assign 4 GB of memory to my VMs. I don’t know if all of it is being used by the applications but no one complains. ·         I take the minimum system requirements and add 50% more. ·         I go with the recommendations provided by my software vendor.   In reality correctly sizing a virtual machine requires significant effort to monitor the memory usage of the applications. Since this is not done in most environments, VMs are usually over-provisioned in terms of memory. In other words, a SQL Server VM that is assigned 4 GB of memory may not need to use 4 GB.   How does Dynamic Memory help?   Dynamic Memory improves the memory utilization by removing the requirement to determine the memory need for an application. Hyper-V determines the memory needed by applications in the VM by evaluating the memory usage information in the guest with Dynamic Memory. VMs can start with a small amount of memory and they can be assigned more memory dynamically based on the workload of applications running inside.   Overview of Dynamic Memory Concepts   ·         Startup Memory: Startup Memory is the starting amount of memory when Dynamic Memory is enabled for a VM. Dynamic Memory will make sure that this amount of memory is always assigned to the VMs by default.   ·         Maximum Memory: Maximum Memory specifies the maximum amount of memory that a VM can grow to with Dynamic Memory. ·         Memory Demand: Memory Demand is the amount determined by Dynamic Memory as the memory needed by the applications in the VM. In Windows Server 2008 R2 SP1, this is equal to the total amount of committed memory of the VM. ·         Memory Buffer: Memory Buffer is the amount of memory assigned to the VMs in addition to their memory demand to satisfy immediate memory requirements and file cache needs.   Once Dynamic Memory is enabled for a VM, it will start with the “Startup Memory”. After the boot process Dynamic Memory will determine the “Memory Demand” of the VM. Based on this memory demand it will determine the amount of “Memory Buffer” that needs to be assigned to the VM. Dynamic Memory will assign the total of “Memory Demand” and “Memory Buffer” to the VM as long as this value is less than “Maximum Memory” and as long as physical memory is available on the host.   What happens when there is not enough physical memory available on the host?   Once there is not enough physical memory on the host to satisfy VM needs, Dynamic Memory will assign less than needed amount of memory to the VMs based on their importance. A concept known as “Memory Weight” is used to determine how much VMs should be penalized based on their needed amount of memory. “Memory Weight” is a configuration setting on the VM. It can be configured to be higher for the VMs with high performance requirements. Under high memory pressure on the host, the “Memory Weight” of the VMs are evaluated in a relative manner and the VMs with lower relative “Memory Weight” will be penalized more than the ones with higher “Memory Weight”.   Dynamic Memory Configuration   Based on these concepts “Startup Memory”, “Maximum Memory”, “Memory Buffer” and “Memory Weight” can be configured as shown below in Windows Server 2008 R2 SP1 Hyper-V Manager. Memory Demand is automatically calculated by Dynamic Memory once VMs start running.     Dynamic Memory Monitoring    In Windows Server 2008 R2 SP1, Hyper-V Manager displays the memory status of VMs in the following three columns:         ·         Assigned Memory represents the current physical memory assigned to the VM. In regular conditions this will be equal to the sum of “Memory Demand” and “Memory Buffer” assigned to the VM. When there is not enough memory on the host, this value can go below the Memory Demand determined for the VM. ·         Memory Demand displays the current “Memory Demand” determined for the VM. ·         Memory Status displays the current memory status of the VM. This column can represent three values for a VM: o   OK: In this condition the VM is assigned the total of Memory Demand and Memory Buffer it needs. o   Low: In this condition the VM is assigned all the Memory Demand and a certain percentage of the Memory Buffer it needs. o   Warning: In this condition the VM is assigned a lower memory than its Memory Demand. When VMs are running in this condition, it’s likely that they will exhibit performance problems due to internal paging happening in the VM.    So far so good! But how does it work with SQL Server?   SQL Server is aggressive in terms of memory usage for good reasons. This raises the question: How do SQL Server and Dynamic Memory work together? To understand the full story, we’ll first need to understand how SQL Server Memory Management works. This will be covered in our second post in “SQL and Dynamic Memory” series. Meanwhile if you want to dive deeper into Dynamic Memory you can check the below posts from the Windows Virtualization Team Blog:   http://blogs.technet.com/virtualization/archive/2010/03/18/dynamic-memory-coming-to-hyper-v.aspx   http://blogs.technet.com/virtualization/archive/2010/03/25/dynamic-memory-coming-to-hyper-v-part-2.aspx   http://blogs.technet.com/virtualization/archive/2010/04/07/dynamic-memory-coming-to-hyper-v-part-3.aspx   http://blogs.technet.com/b/virtualization/archive/2010/04/21/dynamic-memory-coming-to-hyper-v-part-4.aspx   http://blogs.technet.com/b/virtualization/archive/2010/05/20/dynamic-memory-coming-to-hyper-v-part-5.aspx   http://blogs.technet.com/b/virtualization/archive/2010/07/12/dynamic-memory-coming-to-hyper-v-part-6.aspx   - Serdar Sutay   Originally posted at http://blogs.msdn.com/b/sqlosteam/

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• How to deal with transport level security policy with OSB

  - by Jian Liang

  Recently, we received a use case for Oracle Service Bus (OSB) 11gPS4 to consume a Web Service which is secured by HTTP transport level security policy. The WSDL of the remote web service looks like following where the part marked in red shows the security policy: <?xml version='1.0' encoding='UTF-8'?> <definitions xmlns:wssutil="http://docs.oasis-open.org/wss/2004/01/oasis-200401-wss-wssecurity-utility-1.0.xsd" xmlns:wsp="http://schemas.xmlsoap.org/ws/2004/09/policy" xmlns:soap="http://schemas.xmlsoap.org/wsdl/soap/" xmlns:tns="https://httpsbasicauth" xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns="http://schemas.xmlsoap.org/wsdl/" targetNamespace="https://httpsbasicauth" name="HttpsBasicAuthService"> <wsp:UsingPolicy wssutil:Required="true"/> <wsp:Policy wssutil:Id="WSHttpBinding_IPartyServicePortType_policy"> <wsp:ExactlyOne> <wsp:All> <ns1:TransportBinding xmlns:ns1="http://schemas.xmlsoap.org/ws/2005/07/securitypolicy"> <wsp:Policy> <ns1:TransportToken> <wsp:Policy> <ns1:HttpsToken RequireClientCertificate="false"/> </wsp:Policy> </ns1:TransportToken> <ns1:AlgorithmSuite> <wsp:Policy> <ns1:Basic256/> </wsp:Policy> </ns1:AlgorithmSuite> <ns1:Layout> <wsp:Policy> <ns1:Strict/> </wsp:Policy> </ns1:Layout> </wsp:Policy> </ns1:TransportBinding> <ns2:UsingAddressing xmlns:ns2="http://www.w3.org/2006/05/addressing/wsdl"/> </wsp:All> </wsp:ExactlyOne> </wsp:Policy> <types> <xsd:schema> <xsd:import namespace="https://proxyhttpsbasicauth" schemaLocation="http://localhost:7001/WS/HttpsBasicAuthService?xsd=1"/> </xsd:schema> <xsd:schema> <xsd:import namespace="https://httpsbasicauth" schemaLocation="http://localhost:7001/WS/HttpsBasicAuthService?xsd=2"/> </xsd:schema> </types> <message name="echoString"> <part name="parameters" element="tns:echoString"/> </message> <message name="echoStringResponse"> <part name="parameters" element="tns:echoStringResponse"/> </message> <portType name="HttpsBasicAuth"> <operation name="echoString"> <input message="tns:echoString"/> <output message="tns:echoStringResponse"/> </operation> </portType> <binding name="HttpsBasicAuthSoapPortBinding" type="tns:HttpsBasicAuth"> <wsp:PolicyReference URI="#WSHttpBinding_IPartyServicePortType_policy"/> <soap:binding transport="http://schemas.xmlsoap.org/soap/http" style="document"/> <operation name="echoString"> <soap:operation soapAction=""/> <input> <soap:body use="literal"/> </input> <output> <soap:body use="literal"/> </output> </operation> </binding> <service name="HttpsBasicAuthService"> <port name="HttpsBasicAuthSoapPort" binding="tns:HttpsBasicAuthSoapPortBinding"> <soap:address location="https://localhost:7002/WS/HttpsBasicAuthService"/> </port> </service> </definitions> The security assertion in the WSDL (marked in red) indicates that this is the HTTP transport level security policy which requires one way SSL with default authentication (aka. basic authenticate with username/password). Normally, there are two ways to handle web service security policy with OSB 11g: Use WebLogic 9.x policy Use OWSM Since OSB doesn’t support WebLogic 9.x WSSP transport level assertion (except for WS transport), when we tried to create the business service based on the imported WSDL, OSB complained with the following message: [OSB Kernel:398133]The service is based on WSDL with Web Services Security Policies that are not natively supported by Oracle Service Bus. Please select OWSM Policies - From OWSM Policy Store option and attach equivalent OWSM security policy. For the Business Service, either you can add the necessary client policies manually by clicking Add button or you can let Oracle Service Bus automatically pick and add compatible client policies by clicking Add Compatible button. Unfortunately, when tried with OWSM, we couldn’t find http_token_policy from OWSM since OSB PS4 doesn’t support OWSM http_token_policy. It seems that we ran into an unsupported situation that no appropriate policy can be used from both WebLogic and OWSM. As this security policy requires one way SSL with basic authentication at the transport level, a possible workaround is to meet the remote service's requirement at transport level without using web service policy. We can simply use OSB to establish SSL connection and provide username/password for authentication at the transport level to the remote web service. In this case, the business service within OSB will be transparent to the web service policy. However, we still need to deal with OSB console’s complaint related to unsupported security policy because the failure of WSDL validation prohibits OSB console to move forward. With the help from OSB Product Management team, we finally came up with the following solutions: Solution 1: OSB PS5 The good news is that the http_token_policy is made available in OSB PS5. With OSB PS5, you can simply add OWSM oracle/wss_http_token_over_ssl_client_policy to the business service. The simplest solution is to upgrade to OSB PS5 where the OWSM solution is provided out of the box. But if you are not in a position where upgrading is an immediate option, you might want to consider other two workaround solutions described below. Solution 2: Modifying WSDL This solution addresses OSB console’s complaint by removing the security policy from the imported WSDL within OSB. Without the security policy, OSB console allows the business service to be created based on modified WSDL.  Please bear in mind, modifying WSDL is done only for the OSB side via OSB console, no change is required on the remote Web Service. The main steps of this solution: Connect to OSB console import the remote WSDL into OSB remove security assertion (the red marked part) from the imported WSDL create a service account. In our sample, we simply take the user weblogic create the business service and check "Basic" for Authentication and select the created service account make sure that OSB consumes the web service via https. This solution requires modifying WSDL. It is suitable for any OSB version (10g or OSB 11g version) prior to PS5 without OWSM. However, modifying WSDL by hand is troublesome as it requires the user to remember that the original WSDL was edited.  It forces you to make the same edit each time you want to re-import the service WSDL when changes occur at the service level. This also prevents you from using UDDI to import WSDL.  Solution 3: Using original WSDL This solution keeps the WSDL intact and ignores the embedded policy by using OWSM. By design, OWSM doesn’t like WSDL with embedded security assertion. Since OWSM doesn’t provide the feature to explicitly ignore the embedded policy from a remote WSDL, in this solution, we use OWSM in a tricky way to ignore the embedded policy. Connect to OSB console import the remote WSDL into OSB create a service account create the business service in which check "Basic" for Authentication and select the created service account as the imported WSDL is intact, the OSB Kernel:398133 error is expected ignore this error message for the moment and navigate to the Policies Page of business service Select “From OWSM Policy Store” and click “Add” button, the list of policies will pop-up Here is the tricky part: select an arbitrary policy, and click “Cancel” Update and save By clicking “Cancel’ button, we didn’t add any OWSM policy to business service, but the embedded policy is ignored. Yes, this is tricky. According to Oracle OSB Product Manager, the future release of OWSM will add a button “None” which allows to ignore the embedded policy explicitly. This solution keeps the imported WSDL intact which is the big advantage over the solution 2. It is suitable for OSB 11g (version prior to PS5) domain with OWSM configured. This blog addressed the unsupported transport level web service security policy with OSB PS4. To summarize, if you are using OSB PS5 or in a position to upgrade to PS5, the recommendation is to use OWSM OOTB transport level security policy directly. With the release prior to 11g PS5, you can consider the solution 2 or 3 depending on if OWSM is configured.

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• HTML5 Form Validation

  - by Stephen.Walther

  The latest versions of Google Chrome (16+), Mozilla Firefox (8+), and Internet Explorer (10+) all support HTML5 client-side validation. It is time to take HTML5 validation seriously. The purpose of the blog post is to describe how you can take advantage of HTML5 client-side validation regardless of the type of application that you are building. You learn how to use the HTML5 validation attributes, how to perform custom validation using the JavaScript validation constraint API, and how to simulate HTML5 validation on older browsers by taking advantage of a jQuery plugin. Finally, we discuss the security issues related to using client-side validation. Using Client-Side Validation Attributes The HTML5 specification discusses several attributes which you can use with INPUT elements to perform client-side validation including the required, pattern, min, max, step, and maxlength attributes. For example, you use the required attribute to require a user to enter a value for an INPUT element. The following form demonstrates how you can make the firstName and lastName form fields required: <!DOCTYPE html> <html > <head> <title>Required Demo</title> </head> <body> <form> <label> First Name: <input required title="First Name is Required!" /> </label> <label> Last Name: <input required title="Last Name is Required!" /> </label> <button>Register</button> </form> </body> </html> If you attempt to submit this form without entering a value for firstName or lastName then you get the validation error message: Notice that the value of the title attribute is used to display the validation error message “First Name is Required!”. The title attribute does not work this way with the current version of Firefox. If you want to display a custom validation error message with Firefox then you need to include an x-moz-errormessage attribute like this: <input required title="First Name is Required!" x-moz-errormessage="First Name is Required!" /> The pattern attribute enables you to validate the value of an INPUT element against a regular expression. For example, the following form includes a social security number field which includes a pattern attribute: <!DOCTYPE html> <html xmlns="http://www.w3.org/1999/xhtml"> <head> <title>Pattern</title> </head> <body> <form> <label> Social Security Number: <input required pattern="^d{3}-d{2}-d{4}$" title="###-##-####" /> </label> <button>Register</button> </form> </body> </html> The regular expression in the form above requires the social security number to match the pattern ###-##-####: Notice that the input field includes both a pattern and a required validation attribute. If you don’t enter a value then the regular expression is never triggered. You need to include the required attribute to force a user to enter a value and cause the value to be validated against the regular expression. Custom Validation You can take advantage of the HTML5 constraint validation API to perform custom validation. You can perform any custom validation that you need. The only requirement is that you write a JavaScript function. For example, when booking a hotel room, you might want to validate that the Arrival Date is in the future instead of the past: <!DOCTYPE html> <html xmlns="http://www.w3.org/1999/xhtml"> <head> <title>Constraint Validation API</title> </head> <body> <form> <label> Arrival Date: <input id="arrivalDate" type="date" required /> </label> <button>Submit Reservation</button> </form> <script type="text/javascript"> var arrivalDate = document.getElementById("arrivalDate"); arrivalDate.addEventListener("input", function() { var value = new Date(arrivalDate.value); if (value < new Date()) { arrivalDate.setCustomValidity("Arrival date must be after now!"); } else { arrivalDate.setCustomValidity(""); } }); </script> </body> </html> The form above contains an input field named arrivalDate. Entering a value into the arrivalDate field triggers the input event. The JavaScript code adds an event listener for the input event and checks whether the date entered is greater than the current date. If validation fails then the validation error message “Arrival date must be after now!” is assigned to the arrivalDate input field by calling the setCustomValidity() method of the validation constraint API. Otherwise, the validation error message is cleared by calling setCustomValidity() with an empty string. HTML5 Validation and Older Browsers But what about older browsers? For example, what about Apple Safari and versions of Microsoft Internet Explorer older than Internet Explorer 10? What the world really needs is a jQuery plugin which provides backwards compatibility for the HTML5 validation attributes. If a browser supports the HTML5 validation attributes then the plugin would do nothing. Otherwise, the plugin would add support for the attributes. Unfortunately, as far as I know, this plugin does not exist. I have not been able to find any plugin which supports both the required and pattern attributes for older browsers, but does not get in the way of these attributes in the case of newer browsers. There are several jQuery plugins which provide partial support for the HTML5 validation attributes including: · jQuery Validation — http://docs.jquery.com/Plugins/Validation · html5Form — http://www.matiasmancini.com.ar/jquery-plugin-ajax-form-validation-html5.html · h5Validate — http://ericleads.com/h5validate/ The jQuery Validation plugin – the most popular JavaScript validation library – supports the HTML5 required attribute, but it does not support the HTML5 pattern attribute. Likewise, the html5Form plugin does not support the pattern attribute. The h5Validate plugin provides the best support for the HTML5 validation attributes. The following page illustrates how this plugin supports both the required and pattern attributes: <!DOCTYPE html> <html xmlns="http://www.w3.org/1999/xhtml"> <head> <title>h5Validate</title> <style type="text/css"> .validationError { border: solid 2px red; } .validationValid { border: solid 2px green; } </style> </head> <body> <form id="customerForm"> <label> First Name: <input id="firstName" required /> </label> <label> Social Security Number: <input id="ssn" required pattern="^d{3}-d{2}-d{4}$" title="Expected pattern is ###-##-####" /> </label> <input type="submit" /> </form> <script type="text/javascript" src="Scripts/jquery-1.4.4.min.js"></script> <script type="text/javascript" src="Scripts/jquery.h5validate.js"></script> <script type="text/javascript"> // Enable h5Validate plugin $("#customerForm").h5Validate({ errorClass: "validationError", validClass: "validationValid" }); // Prevent form submission when errors $("#customerForm").submit(function (evt) { if ($("#customerForm").h5Validate("allValid") === false) { evt.preventDefault(); } }); </script> </body> </html> When an input field fails validation, the validationError CSS class is applied to the field and the field appears with a red border. When an input field passes validation, the validationValid CSS class is applied to the field and the field appears with a green border. From the perspective of HTML5 validation, the h5Validate plugin is the best of the plugins. It adds support for the required and pattern attributes to browsers which do not natively support these attributes such as IE9. However, this plugin does not include everything in my wish list for a perfect HTML5 validation plugin. Here’s my wish list for the perfect back compat HTML5 validation plugin: 1. The plugin would disable itself when used with a browser which natively supports HTML5 validation attributes. The plugin should not be too greedy – it should not handle validation when a browser could do the work itself. 2. The plugin should simulate the same user interface for displaying validation error messages as the user interface displayed by browsers which natively support HTML5 validation. Chrome, Firefox, and Internet Explorer all display validation errors in a popup. The perfect plugin would also display a popup. 3. Finally, the plugin would add support for the setCustomValidity() method and the other methods of the HTML5 validation constraint API. That way, you could implement custom validation in a standards compatible way and you would know that it worked across all browsers both old and new. Security It would be irresponsible of me to end this blog post without mentioning the issue of security. It is important to remember that any client-side validation — including HTML5 validation — can be bypassed. You should use client-side validation with the intention to create a better user experience. Client validation is great for providing a user with immediate feedback when the user is in the process of completing a form. However, client-side validation cannot prevent an evil hacker from submitting unexpected form data to your web server. You should always enforce your validation rules on the server. The only way to ensure that a required field has a value is to verify that the required field has a value on the server. The HTML5 required attribute does not guarantee anything. Summary The goal of this blog post was to describe the support for validation contained in the HTML5 standard. You learned how to use both the required and the pattern attributes in an HTML5 form. We also discussed how you can implement custom validation by taking advantage of the setCustomValidity() method. Finally, I discussed the available jQuery plugins for adding support for the HTM5 validation attributes to older browsers. Unfortunately, I am unaware of any jQuery plugin which provides a perfect solution to the problem of backwards compatibility.

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• SQL Server and Hyper-V Dynamic Memory - Part 1

  - by SQLOS Team

  SQL and Dynamic Memory Blog Post Series   Hyper-V Dynamic Memory is a new feature in Windows Server 2008 R2 SP1 that allows the memory assigned to guest virtual machines to vary according to demand. Using this feature with SQL Server is supported, but how well does it work in an environment where available memory can vary dynamically, especially since SQL Server likes memory, and is not very eager to let go of it? The next three posts will look at this question in detail. In Part 1 Serdar Sutay, a program manager in the Windows Hyper-V team, introduces Dynamic Memory with an overview of the basic architecture, configuration and monitoring concepts. In subsequent parts we will look at SQL Server memory handling, and develop some guidelines on using SQL Server with Dynamic Memory.   Part 1: Dynamic Memory Introduction   In virtualized environments memory is often the bottleneck for reaching higher VM densities. In Windows Server 2008 R2 SP1 Hyper-V introduced a new feature “Dynamic Memory” to improve VM densities on Hyper-V hosts. Dynamic Memory increases the memory utilization in virtualized environments by enabling VM memory to be changed dynamically when the VM is running.   This brings up the question of how to utilize this feature with SQL Server VMs as SQL Server performance is very sensitive to the memory being used. In the next three posts we’ll discuss the internals of Dynamic Memory, SQL Server Memory Management and how to use Dynamic Memory with SQL Server VMs.   Memory Utilization Efficiency in Virtualized Environments   The primary reason memory is usually the bottleneck for higher VM densities is that users tend to be generous when assigning memory to their VMs. Here are some memory sizing practices we’ve heard from customers:   ·         I assign 4 GB of memory to my VMs. I don’t know if all of it is being used by the applications but no one complains. ·         I take the minimum system requirements and add 50% more. ·         I go with the recommendations provided by my software vendor.   In reality correctly sizing a virtual machine requires significant effort to monitor the memory usage of the applications. Since this is not done in most environments, VMs are usually over-provisioned in terms of memory. In other words, a SQL Server VM that is assigned 4 GB of memory may not need to use 4 GB.   How does Dynamic Memory help?   Dynamic Memory improves the memory utilization by removing the requirement to determine the memory need for an application. Hyper-V determines the memory needed by applications in the VM by evaluating the memory usage information in the guest with Dynamic Memory. VMs can start with a small amount of memory and they can be assigned more memory dynamically based on the workload of applications running inside.   Overview of Dynamic Memory Concepts   ·         Startup Memory: Startup Memory is the starting amount of memory when Dynamic Memory is enabled for a VM. Dynamic Memory will make sure that this amount of memory is always assigned to the VMs by default.   ·         Maximum Memory: Maximum Memory specifies the maximum amount of memory that a VM can grow to with Dynamic Memory. ·         Memory Demand: Memory Demand is the amount determined by Dynamic Memory as the memory needed by the applications in the VM. In Windows Server 2008 R2 SP1, this is equal to the total amount of committed memory of the VM. ·         Memory Buffer: Memory Buffer is the amount of memory assigned to the VMs in addition to their memory demand to satisfy immediate memory requirements and file cache needs.   Once Dynamic Memory is enabled for a VM, it will start with the “Startup Memory”. After the boot process Dynamic Memory will determine the “Memory Demand” of the VM. Based on this memory demand it will determine the amount of “Memory Buffer” that needs to be assigned to the VM. Dynamic Memory will assign the total of “Memory Demand” and “Memory Buffer” to the VM as long as this value is less than “Maximum Memory” and as long as physical memory is available on the host.   What happens when there is not enough physical memory available on the host?   Once there is not enough physical memory on the host to satisfy VM needs, Dynamic Memory will assign less than needed amount of memory to the VMs based on their importance. A concept known as “Memory Weight” is used to determine how much VMs should be penalized based on their needed amount of memory. “Memory Weight” is a configuration setting on the VM. It can be configured to be higher for the VMs with high performance requirements. Under high memory pressure on the host, the “Memory Weight” of the VMs are evaluated in a relative manner and the VMs with lower relative “Memory Weight” will be penalized more than the ones with higher “Memory Weight”.   Dynamic Memory Configuration   Based on these concepts “Startup Memory”, “Maximum Memory”, “Memory Buffer” and “Memory Weight” can be configured as shown below in Windows Server 2008 R2 SP1 Hyper-V Manager. Memory Demand is automatically calculated by Dynamic Memory once VMs start running.     Dynamic Memory Monitoring    In Windows Server 2008 R2 SP1, Hyper-V Manager displays the memory status of VMs in the following three columns:         ·         Assigned Memory represents the current physical memory assigned to the VM. In regular conditions this will be equal to the sum of “Memory Demand” and “Memory Buffer” assigned to the VM. When there is not enough memory on the host, this value can go below the Memory Demand determined for the VM. ·         Memory Demand displays the current “Memory Demand” determined for the VM. ·         Memory Status displays the current memory status of the VM. This column can represent three values for a VM: o   OK: In this condition the VM is assigned the total of Memory Demand and Memory Buffer it needs. o   Low: In this condition the VM is assigned all the Memory Demand and a certain percentage of the Memory Buffer it needs. o   Warning: In this condition the VM is assigned a lower memory than its Memory Demand. When VMs are running in this condition, it’s likely that they will exhibit performance problems due to internal paging happening in the VM.    So far so good! But how does it work with SQL Server?   SQL Server is aggressive in terms of memory usage for good reasons. This raises the question: How do SQL Server and Dynamic Memory work together? To understand the full story, we’ll first need to understand how SQL Server Memory Management works. This will be covered in our second post in “SQL and Dynamic Memory” series. Meanwhile if you want to dive deeper into Dynamic Memory you can check the below posts from the Windows Virtualization Team Blog:   http://blogs.technet.com/virtualization/archive/2010/03/18/dynamic-memory-coming-to-hyper-v.aspx   http://blogs.technet.com/virtualization/archive/2010/03/25/dynamic-memory-coming-to-hyper-v-part-2.aspx   http://blogs.technet.com/virtualization/archive/2010/04/07/dynamic-memory-coming-to-hyper-v-part-3.aspx   http://blogs.technet.com/b/virtualization/archive/2010/04/21/dynamic-memory-coming-to-hyper-v-part-4.aspx   http://blogs.technet.com/b/virtualization/archive/2010/05/20/dynamic-memory-coming-to-hyper-v-part-5.aspx   http://blogs.technet.com/b/virtualization/archive/2010/07/12/dynamic-memory-coming-to-hyper-v-part-6.aspx   - Serdar Sutay   Originally posted at http://blogs.msdn.com/b/sqlosteam/

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• Calling Web Service Functions Asynchronously from a Web Page

  - by SGWellens

  Over on the Asp.Net forums where I moderate, a user had a problem calling a Web Service from a web page asynchronously. I tried his code on my machine and was able to reproduce the problem. I was able to solve his problem, but only after taking the long scenic route through some of the more perplexing nuances of Web Services and Proxies. Here is the fascinating story of that journey. Start with a simple Web Service     public class Service1 : System.Web.Services.WebService    {        [WebMethod]        public string HelloWorld()        {            // sleep 10 seconds            System.Threading.Thread.Sleep(10 * 1000);            return "Hello World";        }    } The 10 second delay is added to make calling an asynchronous function more apparent. If you don't call the function asynchronously, it takes about 10 seconds for the page to be rendered back to the client. If the call is made from a Windows Forms application, the application freezes for about 10 seconds. Add the web service to a web site. Right-click the project and select "Add Web Reference…" Next, create a web page to call the Web Service. Note: An asp.net web page that calls an 'Async' method must have the Async property set to true in the page's header: <%@ Page Language="C#"          AutoEventWireup="true"          CodeFile="Default.aspx.cs"          Inherits="_Default"           Async='true'  %> Here is the code to create the Web Service proxy and connect the event handler. Shrewdly, we make the proxy object a member of the Page class so it remains instantiated between the various events. public partial class _Default : System.Web.UI.Page {    localhost.Service1 MyService;  // web service proxy     // ---- Page_Load ---------------------------------     protected void Page_Load(object sender, EventArgs e)    {        MyService = new localhost.Service1();        MyService.HelloWorldCompleted += EventHandler;          } Here is the code to invoke the web service and handle the event:     // ---- Async and EventHandler (delayed render) --------------------------     protected void ButtonHelloWorldAsync_Click(object sender, EventArgs e)    {        // blocks        ODS("Pre HelloWorldAsync...");        MyService.HelloWorldAsync();        ODS("Post HelloWorldAsync");    }    public void EventHandler(object sender, localhost.HelloWorldCompletedEventArgs e)    {        ODS("EventHandler");        ODS("    " + e.Result);    }     // ---- ODS ------------------------------------------------    //    // Helper function: Output Debug String     public static void ODS(string Msg)    {        String Out = String.Format("{0}  {1}", DateTime.Now.ToString("hh:mm:ss.ff"), Msg);        System.Diagnostics.Debug.WriteLine(Out);    } I added a utility function I use a lot: ODS (Output Debug String). Rather than include the library it is part of, I included it in the source file to keep this example simple. Fire up the project, open up a debug output window, press the button and we get this in the debug output window: 11:29:37.94 Pre HelloWorldAsync... 11:29:37.94 Post HelloWorldAsync 11:29:48.94 EventHandler 11:29:48.94 Hello World   Sweet. The asynchronous call was made and returned immediately. About 10 seconds later, the event handler fires and we get the result. Perfect….right? Not so fast cowboy. Watch the browser during the call: What the heck? The page is waiting for 10 seconds. Even though the asynchronous call returned immediately, Asp.Net is waiting for the event to fire before it renders the page. This is NOT what we wanted. I experimented with several techniques to work around this issue. Some may erroneously describe my behavior as 'hacking' but, since no ingesting of Twinkies was involved, I do not believe hacking is the appropriate term. If you examine the proxy that was automatically created, you will find a synchronous call to HelloWorld along with an additional set of methods to make asynchronous calls. I tried the other asynchronous method supplied in the proxy:     // ---- Begin and CallBack ----------------------------------     protected void ButtonBeginHelloWorld_Click(object sender, EventArgs e)    {        ODS("Pre BeginHelloWorld...");        MyService.BeginHelloWorld(AsyncCallback, null);        ODS("Post BeginHelloWorld");    }    public void AsyncCallback(IAsyncResult ar)    {        String Result = MyService.EndHelloWorld(ar);         ODS("AsyncCallback");        ODS("    " + Result);    } The BeginHelloWorld function in the proxy requires a callback function as a parameter. I tested it and the debug output window looked like this: 04:40:58.57 Pre BeginHelloWorld... 04:40:58.57 Post BeginHelloWorld 04:41:08.58 AsyncCallback 04:41:08.58 Hello World It works the same as before except for one critical difference: The page rendered immediately after the function call. I was worried the page object would be disposed after rendering the page but the system was smart enough to keep the page object in memory to handle the callback. Both techniques have a use: Delayed Render: Say you want to verify a credit card, look up shipping costs and confirm if an item is in stock. You could have three web service calls running in parallel and not render the page until all were finished. Nice. You can send information back to the client as part of the rendered page when all the services are finished. Immediate Render: Say you just want to start a service running and return to the client. You can do that too. However, the page gets sent to the client before the service has finished running so you will not be able to update parts of the page when the service finishes running. Summary: YourFunctionAsync() and an EventHandler will not render the page until the handler fires. BeginYourFunction() and a CallBack function will render the page as soon as possible. I found all this to be quite interesting and did a lot of searching and researching for documentation on this subject….but there isn't a lot out there. The biggest clues are the parameters that can be sent to the WSDL.exe program: http://msdn.microsoft.com/en-us/library/7h3ystb6(VS.100).aspx Two parameters are oldAsync and newAsync. OldAsync will create the Begin/End functions; newAsync will create the Async/Event functions. Caveat: I haven't tried this but it was stated in this article. I'll leave confirming this as an exercise for the student J. Included Code: I'm including the complete test project I created to verify the findings. The project was created with VS 2008 SP1. There is a solution file with 3 projects, the 3 projects are: Web Service Asp.Net Application Windows Forms Application To decide which program runs, you right-click a project and select "Set as Startup Project". I created and played with the Windows Forms application to see if it would reveal any secrets. I found that in the Windows Forms application, the generated proxy did NOT include the Begin/Callback functions. Those functions are only generated for Asp.Net pages. Probably for the reasons discussed earlier. Maybe those Microsoft boys and girls know what they are doing. I hope someone finds this useful. Steve Wellens

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• Entity Framework version 1- Brief Synopsis and Tips &ndash; Part 1

  - by Rohit Gupta

  To Do Eager loading use Projections (for e.g. from c in context.Contacts select c, c.Addresses)  or use Include Query Builder Methods (Include(“Addresses”)) If there is multi-level hierarchical Data then to eager load all the relationships use Include Query Builder methods like customers.Include("Order.OrderDetail") to include Order and OrderDetail collections or use customers.Include("Order.OrderDetail.Location") to include all Order, OrderDetail and location collections with a single include statement =========================================================================== If the query uses Joins then Include() Query Builder method will be ignored, use Nested Queries instead If the query does projections then Include() Query Builder method will be ignored Use Address.ContactReference.Load() OR Contact.Addresses.Load() if you need to Deferred Load Specific Entity – This will result in extra round trips to the database ObjectQuery<> cannot return anonymous types... it will return a ObjectQuery<DBDataRecord> Only Include method can be added to Linq Query Methods Any Linq Query method can be added to Query Builder methods. If you need to append a Query Builder Method (other than Include) after a LINQ method  then cast the IQueryable<Contact> to ObjectQuery<Contact> and then append the Query Builder method to it =========================================================================== Query Builder methods are Select, Where, Include Methods which use Entity SQL as parameters e.g. "it.StartDate, it.EndDate" When Query Builder methods do projection then they return ObjectQuery<DBDataRecord>, thus to iterate over this collection use contact.Item[“Name”].ToString() When Linq To Entities methods do projection, they return collection of anonymous types --- thus the collection is strongly typed and supports Intellisense EF Object Context can track changes only on Entities, not on Anonymous types. If you use a Defining Query for a EntitySet then the EntitySet becomes readonly since a Defining Query is the same as a View (which is treated as a ReadOnly by default). However if you want to use this EntitySet for insert/update/deletes then we need to map stored procs (as created in the DB) to the insert/update/delete functions of the Entity in the Designer You can use either Execute method or ToList() method to bind data to datasources/bindingsources If you use the Execute Method then remember that you can traverse through the ObjectResult<> collection (returned by Execute) only ONCE. In WPF use ObservableCollection to bind to data sources , for keeping track of changes and letting EF send updates to the DB automatically. Use Extension Methods to add logic to Entities. For e.g. create extension methods for the EntityObject class. Create a method in ObjectContext Partial class and pass the entity as a parameter, then call this method as desired from within each entity. ================================================================ DefiningQueries and Stored Procedures: For Custom Entities, one can use DefiningQuery or Stored Procedures. Thus the Custom Entity Collection will be populated using the DefiningQuery (of the EntitySet) or the Sproc. If you use Sproc to populate the EntityCollection then the query execution is immediate and this execution happens on the Server side and any filters applied will be applied in the Client App. If we use a DefiningQuery then these queries are composable, meaning the filters (if applied to the entityset) will all be sent together as a single query to the DB, returning only filtered results. If the sproc returns results that cannot be mapped to existing entity, then we first create the Entity/EntitySet in the CSDL using Designer, then create a dummy Entity/EntitySet using XML in the SSDL. When creating a EntitySet in the SSDL for this dummy entity, use a TSQL that does not return any results, but does return the relevant columns e.g. select ContactID, FirstName, LastName from dbo.Contact where 1=2 Also insure that the Entity created in the SSDL uses the SQL DataTypes and not .NET DataTypes. If you are unable to open the EDMX file in the designer then note the Errors ... they will give precise info on what is wrong. The Thrid option is to simply create a Native Query in the SSDL using <Function Name="PaymentsforContact" IsComposable="false">   <CommandText>SELECT ActivityId, Activity AS ActivityName, ImagePath, Category FROM dbo.Activities </CommandText></FuncTion> Then map this Function to a existing Entity. This is a quick way to get a custom Entity which is regular Entity with renamed columns or additional columns (which are computed columns). The disadvantage to using this is that It will return all the rows from the Defining query and any filter (if defined) will be applied only at the Client side (after getting all the rows from DB). If you you DefiningQuery instead then we can use that as a Composable Query. The Fourth option (for mapping a READ stored proc results to a non-existent Entity) is to create a View in the Database which returns all the fields that the sproc also returns, then update the Model so that the model contains this View as a Entity. Then map the Read Sproc to this View Entity. The other option would be to simply create the View and remove the sproc altogether. ================================================================ To Execute a SProc that does not return a entity, use a EntityCommand to execute that proc. You cannot call a sproc FunctionImport that does not return Entities From Code, the only way is to use SSDL function calls using EntityCommand.  This changes with EntityFramework Version 4 where you can return Scalar Types, Complex Types, Entities or NonQuery ================================================================ UDF when created as a Function in SSDL, we need to set the Name & IsComposable properties for the Function element. IsComposable is always false for Sprocs, for UDF's set this to true. You cannot call UDF "Function" from within code since you cannot import a UDF Function into the CSDL Model (with Version 1 of EF). only stored procedures can be imported and then mapped to a entity ================================================================ Entity Framework requires properties that are involved in association mappings to be mapped in all of the function mappings for the entity (Insert, Update and Delete). Because Payment has an association to Reservation... hence we need to pass both the paymentId and reservationId to the Delete sproc even though just the paymentId is the PK on the Payment Table. ================================================================ When mapping insert, update and delete procs to a Entity, insure that all the three or none are mapped. Further if you have a base class and derived class in the CSDL, then you must map (ins, upd, del) sprocs to all parent and child entities in the inheritance relationship. Note that this limitation that base and derived entity methods must all must be mapped does not apply when you are mapping Read Stored Procedures.... ================================================================ You can write stored procedures SQL directly into the SSDL by creating a Function element in the SSDL and then once created, you can map this Function to a CSDL Entity directly in the designer during Function Import ================================================================ You can do Entity Splitting such that One Entity maps to multiple tables in the DB. For e.g. the Customer Entity currently derives from Contact Entity...in addition it also references the ContactPersonalInfo Entity. One can copy all properties from the ContactPersonalInfo Entity into the Customer Entity and then Delete the CustomerPersonalInfo entity, finall one needs to map the copied properties to the ContactPersonalInfo Table in Table Mapping (by adding another table (ContactPersonalInfo) to the Table Mapping... this is called Entity Splitting. Thus now when you insert a Customer record, it will automatically create SQL to insert records into the Contact, Customers and ContactPersonalInfo tables even though you have a Single Entity called Customer in the CSDL =================================================================== There is Table by Type Inheritance where another EDM Entity can derive from another EDM entity and absorb the inherted entities properties, for example in the Break Away Geek Adventures EDM, the Customer entity derives (inherits) from the Contact Entity and absorbs all the properties of Contact entity. Thus when you create a Customer Entity in Code and then call context.SaveChanges the Object Context will first create the TSQL to insert into the Contact Table followed by a TSQL to insert into the Customer table =================================================================== Then there is the Table per Hierarchy Inheritance..... where different types are created based on a condition (similar applying a condition to filter a Entity to contain filtered records)... the diference being that the filter condition populates a new Entity Type (derived from the base Entity). In the BreakAway sample the example is Lodging Entity which is a Abstract Entity and Then Resort and NonResort Entities which derive from Lodging Entity and records are filtered based on the value of the Resort Boolean field =================================================================== Then there is Table per Concrete Type Hierarchy where we create a concrete Entity for each table in the database. In the BreakAway sample there is a entity for the Reservation table and another Entity for the OldReservation table even though both the table contain the same number of fields. The OldReservation Entity can then inherit from the Reservation Entity and configure the OldReservation Entity to remove all Scalar Properties from the Entity (since it inherits the properties from Reservation and filters based on ReservationDate field) =================================================================== Complex Types (Complex Properties) Entities in EF can also contain Complex Properties (in addition to Scalar Properties) and these Complex Properties reference a ComplexType (not a EntityType) DropdownList, ListBox, RadioButtonList, CheckboxList, Bulletedlist are examples of List server controls (not data bound controls) these controls cannot use Complex properties during databinding, they need Scalar Properties. So if a Entity contains Complex properties and you need to bind those to list server controls then use projections to return Scalar properties and bind them to the control (the disadvantage is that projected collections are not tracked by the Object Context and hence cannot persist changes to the projected collections bound to controls) ObjectDataSource and EntityDataSource do account for Complex properties and one can bind entities with Complex Properties to Data Source controls and they will be tracked for changes... with no additional plumbing needed to persist changes to these collections bound to controls So DataBound controls like GridView, FormView need to use EntityDataSource or ObjectDataSource as a datasource for entities that contain Complex properties so that changes to the datasource done using the GridView can be persisted to the DB (enabling the controls for updates)....if you cannot use the EntityDataSource you need to flatten the ComplexType Properties using projections With EF Version 4 ComplexTypes are supported by the Designer and can add/remove/compose Complex Types directly using the Designer =================================================================== Conditional Mapping ... is like Table per Hierarchy Inheritance where Entities inherit from a base class and then used conditions to populate the EntitySet (called conditional Mapping). Conditional Mapping has limitations since you can only use =, is null and IS NOT NULL Conditions to do conditional mapping. If you need more operators for filtering/mapping conditionally then use QueryView(or possibly Defining Query) to create a readonly entity. QueryView are readonly by default... the EntitySet created by the QueryView is enabled for change tracking by the ObjectContext, however the ObjectContext cannot create insert/update/delete TSQL statements for these Entities when SaveChanges is called since it is QueryView. One way to get around this limitation is to map stored procedures for the insert/update/delete operations in the Designer. =================================================================== Difference between QueryView and Defining Query : QueryView is defined in the (MSL) Mapping File/section of the EDM XML, whereas the DefiningQuery is defined in the store schema (SSDL). QueryView is written using Entity SQL and is this database agnostic and can be used against any database/Data Layer. DefiningQuery is written using Database Lanaguage i.e. TSQL or PSQL thus you have more control =================================================================== Performance: Lazy loading is deferred loading done automatically. lazy loading is supported with EF version4 and is on by default. If you need to turn it off then use context.ContextOptions.lazyLoadingEnabled = false To improve Performance consider PreCompiling the ObjectQuery using the CompiledQuery.Compile method

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• Add Free Google Apps to Your Website or Blog

  - by Matthew Guay

  Would you like to have an email address from your own domain, but prefer Gmail’s interface and integration with Google Docs?  Here’s how you can add the free Google Apps Standard to your site and get the best of both worlds. Note: To signup for Google Apps and get it setup on your domain, you will need to be able to add info to your WordPress blog or change Domain settings manually. Getting Started Head to the Google Apps signup page (link below), and click the Get Started button on the right.  Note that we are signing up for the free Google Apps which allows a max of 50 users; if you need more than 50 email addresses for your domain, you can choose Premiere Edition instead for $50/year. Select that you are the Administrator of the domain, and enter the domain or subdomain you want to use with Google Apps.  Here we’re adding Google Apps to the techinch.com site, but we could instead add Apps to mail.techinch.com if needed…click Get Started. Enter your name, phone number, an existing email address, and other Administrator information.  The Apps signup page also includes some survey questions about your organization, but you only have to fill in the required fields. On the next page, enter a username and password for the administrator account.  Note that the user name will also be the administrative email address as [email protected]. Now you’re ready to authenticate your Google Apps account with your domain.  The steps are slightly different depending on whether your site is on WordPress.com or on your own hosting service or server, so we’ll show how to do it both ways.   Authenticate and Integrate Google Apps with WordPress.com To add Google Apps to a domain you have linked to your WordPress.com blog, select Change yourdomain.com CNAME record and click Continue. Copy the code under #2, which should be something like googleabcdefg123456.  Do not click the button at the bottom; wait until we’ve completed the next step.   Now, in a separate browser window or tab, open your WordPress Dashboard.  Click the arrow beside Upgrades, and select Domains from the menu. Click the Edit DNS link beside the domain name you’re adding to Google Apps. Scroll down to the Google Apps section, and paste your code from Google Apps into the verification code field.  Click Generate DNS records when you’re done. This will add the needed DNS settings to your records in the box above the Google Apps section.  Click Save DNS records. Now, go back to the Google Apps signup page, and click I’ve completed the steps above. Authenticate Google Apps on Your Own Server If your website is hosted on your own server or hosting account, you’ll need to take a few more steps to add Google Apps to your domain.  You can add a CNAME record to your domain host using the same information that you would use with a WordPress account, or you can upload an HTML file to your site’s main directory.  In this test we’re going to upload an HTML file to our site for verification. Copy the code under #1, which should be something like googleabcdefg123456.  Do not click the button at the bottom; wait until we’ve completed the next step first. Create a new HTML file and paste the code in it.  You can do this easily in Notepad: create a new document, paste the code, and then save as googlehostedservice.html.  Make sure to select the type as All Files or otherwise the file will have a .txt extension. Upload this file to your web server via FTP or a web dashboard for your site.  Make sure it is in the top level of your site’s directory structure, and try visiting it at yoursite.com/googlehostedservice.html. Now, go back to the Google Apps signup page, and click I’ve completed the steps above. Setup Your Email on Google Apps When this is done, your Google Apps account should be activated and ready to finish setting up.  Google Apps will offer to launch a guide to step you through the rest of the process; you can click Launch guide if you want, or click Skip this guide to continue on your own and go directly to the Apps dashboard.   If you choose to open the guide, you’ll be able to easily learn the ropes of Google Apps administration.  Once you’ve completed the tutorial, you’ll be taken to the Google Apps dashboard. Most of the Google Apps will be available for immediate use, but Email may take a bit more setup.  Click Activate email to get your Gmail-powered email running on your domain.    Add Google MX Records to Your Server You will need to add Google MX records to your domain registrar in order to have your mail routed to Google.  If your domain is hosted on WordPress.com, you’ve already made these changes so simply click I have completed these steps.  Otherwise, you’ll need to manually add these records before clicking that button.   Adding MX Entries is fairly easy, but the steps may depend on your hosting company or registrar.  With some hosts, you may have to contact support to have them add the MX records for you.  Our site’s host uses the popular cPanel for website administration, so here’s how we added the MX Entries through cPanel. Add MX Entries through cPanel Login to your site’s cPanel, and click the MX Entry link under Mail. Delete any existing MX Records for your domain or subdomain first to avoid any complications or interactions with Google Apps.  If you think you may want to revert to your old email service in the future, save a copy of the records so you can switch back if you need. Now, enter the MX Records that Google listed.  Here’s our account after we added all of the entries to our account. Finally, return to your Google Apps Dashboard and click the I have completed these steps button at the bottom of the page. Activating Service You’re now officially finished activating and setting up your Google Apps account.  Google will first have to check the MX records for your domain; this only took around an hour in our test, but Google warns it can take up to 48 hours in some cases. You may then see that Google is updating its servers with your account information.  Once again, this took much less time than Google’s estimate. When everything’s finished, you can click the link to access the inbox of your new Administrator email account in Google Apps. Welcome to Gmail … at your own domain!  All of the Google Apps work just the same in this version as they do in the public @gmail.com version, so you should feel right at home. You can return to the Google Apps dashboard from the Administrative email account by clicking the Manage this domain at the top right. In the Dashboard, you can easily add new users and email accounts, as well as change settings in your Google Apps account and add your site’s branding to your Apps. Your Google Apps will work just like their standard @gmail.com counterparts.  Here’s an example of an inbox customized with the techinch logo and a Gmail theme. Links to Remember Here are the common links to your Google Apps online.  Substitute your domain or subdomain for yourdomain.com. Dashboard https://www.google.com/a/cpanel/yourdomain.com Email https://mail.google.com/a/yourdomain.com Calendar https://www.google.com/calendar/hosted/yourdomain.com Docs https://docs.google.com/a/yourdomain.com Sites https://sites.google.com/a/yourdomain.com Conclusion Google Apps offers you great webapps and webmail for your domain, and let’s you take advantage of Google’s services while still maintaining the professional look of your own domain.  Setting up your account can be slightly complicated, but once it’s finished, it will run seamlessly and you’ll never have to worry about email or collaboration with your team again. Signup for the free Google Apps Standard Similar Articles Productive Geek Tips Mysticgeek Blog: Create Your Own Simple iGoogle GadgetAccess Your Favorite Google Services in Chrome the Easy WayRevo Uninstaller Pro [REVIEW]Mysticgeek Blog: A Look at Internet Explorer 8 Beta 1 on Windows XPFind Similar Websites in Google Chrome TouchFreeze Alternative in AutoHotkey The Icy Undertow Desktop Windows Home Server – Backup to LAN The Clear & Clean Desktop Use This Bookmarklet to Easily Get Albums Use AutoHotkey to Assign a Hotkey to a Specific Window Latest Software Reviews Tinyhacker Random Tips Xobni Plus for Outlook All My Movies 5.9 CloudBerry Online Backup 1.5 for Windows Home Server Snagit 10 Video preview of new Windows Live Essentials 21 Cursor Packs for XP, Vista & 7 Map the Stars with Stellarium Use ILovePDF To Split and Merge PDF Files TimeToMeet is a Simple Online Meeting Planning Tool Easily Create More Bookmark Toolbars in Firefox

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• Metro: Promises

  - by Stephen.Walther

  The goal of this blog entry is to describe the Promise class in the WinJS library. You can use promises whenever you need to perform an asynchronous operation such as retrieving data from a remote website or a file from the file system. Promises are used extensively in the WinJS library. Asynchronous Programming Some code executes immediately, some code requires time to complete or might never complete at all. For example, retrieving the value of a local variable is an immediate operation. Retrieving data from a remote website takes longer or might not complete at all. When an operation might take a long time to complete, you should write your code so that it executes asynchronously. Instead of waiting for an operation to complete, you should start the operation and then do something else until you receive a signal that the operation is complete. An analogy. Some telephone customer service lines require you to wait on hold – listening to really bad music – until a customer service representative is available. This is synchronous programming and very wasteful of your time. Some newer customer service lines enable you to enter your telephone number so the customer service representative can call you back when a customer representative becomes available. This approach is much less wasteful of your time because you can do useful things while waiting for the callback. There are several patterns that you can use to write code which executes asynchronously. The most popular pattern in JavaScript is the callback pattern. When you call a function which might take a long time to return a result, you pass a callback function to the function. For example, the following code (which uses jQuery) includes a function named getFlickrPhotos which returns photos from the Flickr website which match a set of tags (such as “dog” and “funny”): function getFlickrPhotos(tags, callback) { $.getJSON( "http://api.flickr.com/services/feeds/photos_public.gne?jsoncallback=?", { tags: tags, tagmode: "all", format: "json" }, function (data) { if (callback) { callback(data.items); } } ); } getFlickrPhotos("funny, dogs", function(data) { $.each(data, function(index, item) { console.log(item); }); }); The getFlickr() function includes a callback parameter. When you call the getFlickr() function, you pass a function to the callback parameter which gets executed when the getFlicker() function finishes retrieving the list of photos from the Flickr web service. In the code above, the callback function simply iterates through the results and writes each result to the console. Using callbacks is a natural way to perform asynchronous programming with JavaScript. Instead of waiting for an operation to complete, sitting there and listening to really bad music, you can get a callback when the operation is complete. Using Promises The CommonJS website defines a promise like this (http://wiki.commonjs.org/wiki/Promises): “Promises provide a well-defined interface for interacting with an object that represents the result of an action that is performed asynchronously, and may or may not be finished at any given point in time. By utilizing a standard interface, different components can return promises for asynchronous actions and consumers can utilize the promises in a predictable manner.” A promise provides a standard pattern for specifying callbacks. In the WinJS library, when you create a promise, you can specify three callbacks: a complete callback, a failure callback, and a progress callback. Promises are used extensively in the WinJS library. The methods in the animation library, the control library, and the binding library all use promises. For example, the xhr() method included in the WinJS base library returns a promise. The xhr() method wraps calls to the standard XmlHttpRequest object in a promise. The following code illustrates how you can use the xhr() method to perform an Ajax request which retrieves a file named Photos.txt: var options = { url: "/data/photos.txt" }; WinJS.xhr(options).then( function (xmlHttpRequest) { console.log("success"); var data = JSON.parse(xmlHttpRequest.responseText); console.log(data); }, function(xmlHttpRequest) { console.log("fail"); }, function(xmlHttpRequest) { console.log("progress"); } ) The WinJS.xhr() method returns a promise. The Promise class includes a then() method which accepts three callback functions: a complete callback, an error callback, and a progress callback: Promise.then(completeCallback, errorCallback, progressCallback) In the code above, three anonymous functions are passed to the then() method. The three callbacks simply write a message to the JavaScript Console. The complete callback also dumps all of the data retrieved from the photos.txt file. Creating Promises You can create your own promises by creating a new instance of the Promise class. The constructor for the Promise class requires a function which accepts three parameters: a complete, error, and progress function parameter. For example, the code below illustrates how you can create a method named wait10Seconds() which returns a promise. The progress function is called every second and the complete function is not called until 10 seconds have passed: (function () { "use strict"; var app = WinJS.Application; function wait10Seconds() { return new WinJS.Promise(function (complete, error, progress) { var seconds = 0; var intervalId = window.setInterval(function () { seconds++; progress(seconds); if (seconds > 9) { window.clearInterval(intervalId); complete(); } }, 1000); }); } app.onactivated = function (eventObject) { if (eventObject.detail.kind === Windows.ApplicationModel.Activation.ActivationKind.launch) { wait10Seconds().then( function () { console.log("complete") }, function () { console.log("error") }, function (seconds) { console.log("progress:" + seconds) } ); } } app.start(); })(); All of the work happens in the constructor function for the promise. The window.setInterval() method is used to execute code every second. Every second, the progress() callback method is called. If more than 10 seconds have passed then the complete() callback method is called and the clearInterval() method is called. When you execute the code above, you can see the output in the Visual Studio JavaScript Console. Creating a Timeout Promise In the previous section, we created a custom Promise which uses the window.setInterval() method to complete the promise after 10 seconds. We really did not need to create a custom promise because the Promise class already includes a static method for returning promises which complete after a certain interval. The code below illustrates how you can use the timeout() method. The timeout() method returns a promise which completes after a certain number of milliseconds. WinJS.Promise.timeout(3000).then( function(){console.log("complete")}, function(){console.log("error")}, function(){console.log("progress")} ); In the code above, the Promise completes after 3 seconds (3000 milliseconds). The Promise returned by the timeout() method does not support progress events. Therefore, the only message written to the console is the message “complete” after 10 seconds. Canceling Promises Some promises, but not all, support cancellation. When you cancel a promise, the promise’s error callback is executed. For example, the following code uses the WinJS.xhr() method to perform an Ajax request. However, immediately after the Ajax request is made, the request is cancelled. // Specify Ajax request options var options = { url: "/data/photos.txt" }; // Make the Ajax request var request = WinJS.xhr(options).then( function (xmlHttpRequest) { console.log("success"); }, function (xmlHttpRequest) { console.log("fail"); }, function (xmlHttpRequest) { console.log("progress"); } ); // Cancel the Ajax request request.cancel(); When you run the code above, the message “fail” is written to the Visual Studio JavaScript Console. Composing Promises You can build promises out of other promises. In other words, you can compose promises. There are two static methods of the Promise class which you can use to compose promises: the join() method and the any() method. When you join promises, a promise is complete when all of the joined promises are complete. When you use the any() method, a promise is complete when any of the promises complete. The following code illustrates how to use the join() method. A new promise is created out of two timeout promises. The new promise does not complete until both of the timeout promises complete: WinJS.Promise.join([WinJS.Promise.timeout(1000), WinJS.Promise.timeout(5000)]) .then(function () { console.log("complete"); }); The message “complete” will not be written to the JavaScript Console until both promises passed to the join() method completes. The message won’t be written for 5 seconds (5,000 milliseconds). The any() method completes when any promise passed to the any() method completes: WinJS.Promise.any([WinJS.Promise.timeout(1000), WinJS.Promise.timeout(5000)]) .then(function () { console.log("complete"); }); The code above writes the message “complete” to the JavaScript Console after 1 second (1,000 milliseconds). The message is written to the JavaScript console immediately after the first promise completes and before the second promise completes. Summary The goal of this blog entry was to describe WinJS promises. First, we discussed how promises enable you to easily write code which performs asynchronous actions. You learned how to use a promise when performing an Ajax request. Next, we discussed how you can create your own promises. You learned how to create a new promise by creating a constructor function with complete, error, and progress parameters. Finally, you learned about several advanced methods of promises. You learned how to use the timeout() method to create promises which complete after an interval of time. You also learned how to cancel promises and compose promises from other promises.

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• VSNewFile: A Visual Studio Addin to More Easily Add New Items to a Project

  - by InfinitiesLoop

  My first Visual Studio Add-in! Creating add-ins is pretty simple, once you get used to the CommandBar model it is using, which is apparently a general Office suite extensibility mechanism. Anyway, let me first explain my motivation for this. It started out as an academic exercise, as I have always wanted to dip my feet in a little VS extensibility. But I thought of a legitimate need for an add-in, at least in my personal experience, so it took on new life. But I figured I can’t be the only one who has felt this way, so I decided to publish the add-in, and host it on GitHub (VSNewFile on GitHub) hoping to spur contributions. Adding Files the Built-in Way Here’s the problem I wanted to solve. You’re working on a project, and it’s time to add a new file to the project. Whatever it is – a class, script, html page, aspx page, or what-have-you, you go through a menu or keyboard shortcut to get to the “Add New Item” dialog. Typically, you do it by right-clicking the location where you want the file (the project or a folder of it): This brings up a dialog the contains, well, every conceivable type of item you might want to add. It’s all the available item templates, which can result in anywhere from a ton to a veritable sea of choices. To be fair, this dialog has been revamped in Visual Studio 2010, which organizes it a little better than Visual Studio 2008, and adds a search box. It also loads noticeably faster.   To me, this dialog is just getting in my way. If I want to add a JavaScript script to my project, I don’t want to have to hunt for the script template item in this dialog. Yes, it is categorized, and yes, it now has a search box. But still, all this UI to swim through when all I need is a new file in the project. I will name it. I will provide the content, I don’t even need a ‘template’. VS kind of realizes this. In the add menu in a class library project, for example, there is a “Add Class…” choice. But all this really does is select that project item from the dialog by default. You still must wait for the dialog, see it, and type in a name for the file. How is that really any different than hitting F2 on an existing item? It isn’t. Adding Files the Hack Way What I often find myself doing, just to avoid going through this dialog, is to copy and paste an existing file, rename it, then “CTRL-A, DEL” the content. In a few short keystrokes I’ve got my new file. Even if the original file wasn’t the right type, it doesn’t matter – I will rename it anyway, including the extension. It works well enough if the place I am adding the file to doesn’t have much in it already. But if there are a lot of files at that level, it sucks, because the new file will have the name “Copy of xyz”, causing it to be moved into the ‘C’ section of the alphabetically sorted items, which might be far, far away from the original file (and so I tend to try and copy a file that starts with ‘C’ *evil grin*). Using ‘Export Template’ To be completely fair I should at least mention this feature. I’m not even sure if this is new in VS 2010 or not (I think so). But it allows you to export a project item or items, including potential project references required by it. Then it becomes a new item in the available ‘installed templates’. No doubt this is useful to help bootstrap new projects. But that still requires you to go through the ‘New Item’ dialog. Adding Files with VSNewFile So hopefully I have sufficiently defined the problem and got a few of you to think, “Yeah, me too!”… What VSNewFile does is let you skip the dialog entirely by adding project items directly to the context menu. But it does a bit more than that, so do read on. For example, to add a new class, you can right-click the location and pick that option. A new .cs file is instantly added to the project, and the new item is selected and put into the ‘rename’ mode immediately. The default items available are shown here. But you can customize them. You can also customize the content of each template. To do so, you create a directory in your documents folder, ‘VSNewFile Templates’. In there, you drop the templates you want to use, but you name them in a particular way. For example, here’s a template that will add a new item named “Add TITLE”. It will add a project item named “SOMEFILE.foo” (or ‘SOMEFILE1.foo’ if that exists, etc). The format of the file name is: <ORDER>_<KEY>_<BASE FILENAME>_<ICON ID>_<TITLE>.<EXTENTION> Where: <ORDER> is a number that lets you determine the order of the items in the menu (relative to each other). <KEY> is a case sensitive identifier different for each template item. More on that later. <BASE FILENAME> is the default name of the file, which doesn’t matter that much, since they will be renaming it anyway. <ICON ID> is a number the dictates the icon used for the menu item. There are a huge number of built-in choices. More on that later. <TITLE> is the string that will appear in the menu. And, the contents of the file are the default content for the item (the ‘template’). The content of the file can contain anything you want, of course. But it also supports two tokens: %NAMESPACE% and %FILENAME%, which will be replaced with the corresponding values. Here is the content of this sample: testing Namespace = %NAMESPACE% Filename = %FILENAME% I kind went back and forth on this. I could have made it so there’d be an XML or JSON file that defines the templates, instead of cramming all this data into the filename itself. I like the simplicity of this better. It makes it easy to customize since you can literally just throw these files around, copy them from someone else, etc, without worrying about merge data into a central description file, in whatever format. Here’s our new item showing up: Practical Use One immediate thing I am using this for is to make it easier to add very commonly used scripts to my web projects. For example, uh, say, jQuery? :) All I need to do is drop jQuery-1.4.2.js and jQuery-1.4.2.min.js into the templates folder, provide the order, title, etc, and then instantly, I can now add jQuery to any project I have without even thinking about “where is jQuery? Can I copy it from that other project?”   Using the KEY There are two reasons for the ‘key’ portion of the item. First, it allows you to turn off the built-in, default templates, which are: FILE = Add File (generic, empty file) VB = Add VB Class CS = Add C# Class (includes some basic usings) HTML = Add HTML page (includes basic structure, doctype, etc) JS = Add Script (includes an immediately-invoking function closure) To turn one off, just include a file with the name “_<KEY>”. For example, to turn off all the items except our custom one, you do this: The other reason for the key is that there are new Visual Studio Commands created for each one. This makes it possible to bind a keyboard shortcut to one of them. So you could, for example, have a keyboard combination that adds a new web page to your website, or a new CS class to your class library, etc. Here is our sample item showing up in the keyboard bindings option. Even though the contents of the template directory may change from one launch of Visual Studio to the next, the bindings will remain attached to any item with a particular key, thanks to it taking care not to lose keyboard bindings even though the commands are completely recreated each time. The Icon Face ID Visual Studio uses a Microsoft Office style add-in mechanism, I gather. There are a predetermined set of built-in icons available. You can use your own icons when developing add-ins, of course, but I’m no designer. I just wanted to find appropriate-ish icons for the built-in templates, and allow you to choose from an existing built-in icon for your own. Unfortunately, there isn’t a lot out there on the interwebs that helps you figure out what the built-in types are. There’s an MSDN article that describes at length a way to create a program that lists all the icons. But I don’t want to write a program to figure them out! Just show them to me! Sheesh :) Thankfully, someone out there felt the same way, and uses a novel hack to get the icons to show up in an outlook toolbar. He then painstakingly took screenshots of them, one group at a time. It isn’t complete though – there are tens of thousands of icons. But it’s good enough. If anyone has an exhaustive list, please let me, and the rest of the add-in community know. Icon Face ID Reference Installing the Add-in It will work with Visual Studio 2008 and Visual Studio 2010. Just unzip the release into your Documents\Visual Studio 20xx\Addins folder. It contains the binary and the Visual Studio “.addin” file. For example, the path to mine is: C:\Users\InfinitiesLoop\Documents\Visual Studio 2010\Addins Conclusion So that’s it! I hope you find it as useful as I have. It’s on GitHub, so if you’re into this kind of thing, please do fork it and improve it! Reference: VSNewFile on GitHub VSNewFile release on GitHub Icon Face ID Reference

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• SQL SERVER – Weekly Series – Memory Lane – #038

  - by Pinal Dave

  Here is the list of selected articles of SQLAuthority.com across all these years. Instead of just listing all the articles I have selected a few of my most favorite articles and have listed them here with additional notes below it. Let me know which one of the following is your favorite article from memory lane. 2007 CASE Statement in ORDER BY Clause – ORDER BY using Variable This article is as per request from the Application Development Team Leader of my company. His team encountered code where the application was preparing string for ORDER BY clause of the SELECT statement. Application was passing this string as variable to Stored Procedure (SP) and SP was using EXEC to execute the SQL string. This is not good for performance as Stored Procedure has to recompile every time due to EXEC. sp_executesql can do the same task but still not the best performance. SSMS – View/Send Query Results to Text/Grid/Files Results to Text – CTRL + T Results to Grid – CTRL + D Results to File – CTRL + SHIFT + F 2008 Introduction to SPARSE Columns Part 2 I wrote about Introduction to SPARSE Columns Part 1. Let us understand the concept of the SPARSE column in more detail. I suggest you read the first part before continuing reading this article. All SPARSE columns are stored as one XML column in the database. Let us see some of the advantage and disadvantage of SPARSE column. Deferred Name Resolution How come when table name is incorrect SP can be created successfully but when an incorrect column is used SP cannot be created? 2009 Backup Timeline and Understanding of Database Restore Process in Full Recovery Model In general, databases backup in full recovery mode is taken in three different kinds of database files. Full Database Backup Differential Database Backup Log Backup Restore Sequence and Understanding NORECOVERY and RECOVERY While doing RESTORE Operation if you restoring database files, always use NORECOVER option as that will keep the database in a state where more backup file are restored. This will also keep database offline also to prevent any changes, which can create itegrity issues. Once all backup file is restored run RESTORE command with a RECOVERY option to get database online and operational. Four Different Ways to Find Recovery Model for Database Perhaps, the best thing about technical domain is that most of the things can be executed in more than one ways. It is always useful to know about the various methods of performing a single task. Two Methods to Retrieve List of Primary Keys and Foreign Keys of Database When Information Schema is used, we will not be able to discern between primary key and foreign key; we will have both the keys together. In the case of sys schema, we can query the data in our preferred way and can join this table to another table, which can retrieve additional data from the same. Get Last Running Query Based on SPID PID is returns sessions ID of the current user process. The acronym SPID comes from the name of its earlier version, Server Process ID. 2010 SELECT * FROM dual – Dual Equivalent Dual is a table that is created by Oracle together with data dictionary. It consists of exactly one column named “dummy”, and one record. The value of that record is X. You can check the content of the DUAL table using the following syntax. SELECT * FROM dual Identifying Statistics Used by Query Someone asked this question in my training class of query optimization and performance tuning.  “Can I know which statistics were used by my query?” 2011 SQL SERVER – Interview Questions and Answers – Frequently Asked Questions – Day 14 of 31 What are the basic functions for master, msdb, model, tempdb and resource databases? What is the Maximum Number of Index per Table? Explain Few of the New Features of SQL Server 2008 Management Studio Explain IntelliSense for Query Editing Explain MultiServer Query Explain Query Editor Regions Explain Object Explorer Enhancements Explain Activity Monitors SQL SERVER – Interview Questions and Answers – Frequently Asked Questions – Day 15 of 31 What is Service Broker? Where are SQL server Usernames and Passwords Stored in the SQL server? What is Policy Management? What is Database Mirroring? What are Sparse Columns? What does TOP Operator Do? What is CTE? What is MERGE Statement? What is Filtered Index? Which are the New Data Types Introduced in SQL SERVER 2008? SQL SERVER – Interview Questions and Answers – Frequently Asked Questions – Day 16 of 31 What are the Advantages of Using CTE? How can we Rewrite Sub-Queries into Simple Select Statements or with Joins? What is CLR? What are Synonyms? What is LINQ? What are Isolation Levels? What is Use of EXCEPT Clause? What is XPath? What is NOLOCK? What is the Difference between Update Lock and Exclusive Lock? SQL SERVER – Interview Questions and Answers – Frequently Asked Questions – Day 17 of 31 How will you Handle Error in SQL SERVER 2008? What is RAISEERROR? What is RAISEERROR? How to Rebuild the Master Database? What is the XML Datatype? What is Data Compression? What is Use of DBCC Commands? How to Copy the Tables, Schema and Views from one SQL Server to Another? How to Find Tables without Indexes? SQL SERVER – Interview Questions and Answers – Frequently Asked Questions – Day 18 of 31 How to Copy Data from One Table to Another Table? What is Catalog Views? What is PIVOT and UNPIVOT? What is a Filestream? What is SQLCMD? What do you mean by TABLESAMPLE? What is ROW_NUMBER()? What are Ranking Functions? What is Change Data Capture (CDC) in SQL Server 2008? SQL SERVER – Interview Questions and Answers – Frequently Asked Questions – Day 19 of 31 How can I Track the Changes or Identify the Latest Insert-Update-Delete from a Table? What is the CPU Pressure? How can I Get Data from a Database on Another Server? What is the Bookmark Lookup and RID Lookup? What is Difference between ROLLBACK IMMEDIATE and WITH NO_WAIT during ALTER DATABASE? What is Difference between GETDATE and SYSDATETIME in SQL Server 2008? How can I Check that whether Automatic Statistic Update is Enabled or not? How to Find Index Size for Each Index on Table? What is the Difference between Seek Predicate and Predicate? What are Basics of Policy Management? What are the Advantages of Policy Management? SQL SERVER – Interview Questions and Answers – Frequently Asked Questions – Day 20 of 31 What are Policy Management Terms? What is the ‘FILLFACTOR’? Where in MS SQL Server is ’100’ equal to ‘0’? What are Points to Remember while Using the FILLFACTOR Argument? What is a ROLLUP Clause? What are Various Limitations of the Views? What is a Covered index? When I Delete any Data from a Table, does the SQL Server reduce the size of that table? What are Wait Types? How to Stop Log File Growing too Big? If any Stored Procedure is Encrypted, then can we see its definition in Activity Monitor? 2012 Example of Width Sensitive and Width Insensitive Collation Width Sensitive Collation: A single-byte character (half-width) represented as single-byte and the same character represented as a double-byte character (full-width) are when compared are not equal the collation is width sensitive. In this example we have one table with two columns. One column has a collation of width sensitive and the second column has a collation of width insensitive. Find Column Used in Stored Procedure – Search Stored Procedure for Column Name Very interesting conversation about how to find column used in a stored procedure. There are two different characters in the story and both are having a conversation about how to find column in the stored procedure. Here are two part story Part 1 | Part 2 SQL SERVER – 2012 Functions – FORMAT() and CONCAT() – An Interesting Usage Generate Script for Schema and Data – SQL in Sixty Seconds #021 – Video In simple words, in many cases the database move from one place to another place. It is not always possible to back up and restore databases. There are possibilities when only part of the database (with schema and data) has to be moved. In this video we learn that we can easily generate script for schema for data and move from one server to another one. INFORMATION_SCHEMA.COLUMNS and Value Character Maximum Length -1 I often see the value -1 in the CHARACTER_MAXIMUM_LENGTH column of INFORMATION_SCHEMA.COLUMNS table. I understand that the length of any column can be between 0 to large number but I do not get it when I see value in negative (i.e. -1). Any insight on this subject? Reference: Pinal Dave (http://blog.sqlauthority.com) Filed under: Memory Lane, PostADay, SQL, SQL Authority, SQL Query, SQL Server, SQL Tips and Tricks, T SQL, Technology

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• HTML5 Form Validation

  - by Stephen.Walther

  The latest versions of Google Chrome (16+), Mozilla Firefox (8+), and Internet Explorer (10+) all support HTML5 client-side validation. It is time to take HTML5 validation seriously. The purpose of the blog post is to describe how you can take advantage of HTML5 client-side validation regardless of the type of application that you are building. You learn how to use the HTML5 validation attributes, how to perform custom validation using the JavaScript validation constraint API, and how to simulate HTML5 validation on older browsers by taking advantage of a jQuery plugin. Finally, we discuss the security issues related to using client-side validation. Using Client-Side Validation Attributes The HTML5 specification discusses several attributes which you can use with INPUT elements to perform client-side validation including the required, pattern, min, max, step, and maxlength attributes. For example, you use the required attribute to require a user to enter a value for an INPUT element. The following form demonstrates how you can make the firstName and lastName form fields required: <!DOCTYPE html> <html > <head> <title>Required Demo</title> </head> <body> <form> <label> First Name: <input required title="First Name is Required!" /> </label> <label> Last Name: <input required title="Last Name is Required!" /> </label> <button>Register</button> </form> </body> </html> If you attempt to submit this form without entering a value for firstName or lastName then you get the validation error message: Notice that the value of the title attribute is used to display the validation error message “First Name is Required!”. The title attribute does not work this way with the current version of Firefox. If you want to display a custom validation error message with Firefox then you need to include an x-moz-errormessage attribute like this: <input required title="First Name is Required!" x-moz-errormessage="First Name is Required!" /> The pattern attribute enables you to validate the value of an INPUT element against a regular expression. For example, the following form includes a social security number field which includes a pattern attribute: <!DOCTYPE html> <html xmlns="http://www.w3.org/1999/xhtml"> <head> <title>Pattern</title> </head> <body> <form> <label> Social Security Number: <input required pattern="^\d{3}-\d{2}-\d{4}$" title="###-##-####" /> </label> <button>Register</button> </form> </body> </html> The regular expression in the form above requires the social security number to match the pattern ###-##-####: Notice that the input field includes both a pattern and a required validation attribute. If you don’t enter a value then the regular expression is never triggered. You need to include the required attribute to force a user to enter a value and cause the value to be validated against the regular expression. Custom Validation You can take advantage of the HTML5 constraint validation API to perform custom validation. You can perform any custom validation that you need. The only requirement is that you write a JavaScript function. For example, when booking a hotel room, you might want to validate that the Arrival Date is in the future instead of the past: <!DOCTYPE html> <html xmlns="http://www.w3.org/1999/xhtml"> <head> <title>Constraint Validation API</title> </head> <body> <form> <label> Arrival Date: <input id="arrivalDate" type="date" required /> </label> <button>Submit Reservation</button> </form> <script type="text/javascript"> var arrivalDate = document.getElementById("arrivalDate"); arrivalDate.addEventListener("input", function() { var value = new Date(arrivalDate.value); if (value < new Date()) { arrivalDate.setCustomValidity("Arrival date must be after now!"); } else { arrivalDate.setCustomValidity(""); } }); </script> </body> </html> The form above contains an input field named arrivalDate. Entering a value into the arrivalDate field triggers the input event. The JavaScript code adds an event listener for the input event and checks whether the date entered is greater than the current date. If validation fails then the validation error message “Arrival date must be after now!” is assigned to the arrivalDate input field by calling the setCustomValidity() method of the validation constraint API. Otherwise, the validation error message is cleared by calling setCustomValidity() with an empty string. HTML5 Validation and Older Browsers But what about older browsers? For example, what about Apple Safari and versions of Microsoft Internet Explorer older than Internet Explorer 10? What the world really needs is a jQuery plugin which provides backwards compatibility for the HTML5 validation attributes. If a browser supports the HTML5 validation attributes then the plugin would do nothing. Otherwise, the plugin would add support for the attributes. Unfortunately, as far as I know, this plugin does not exist. I have not been able to find any plugin which supports both the required and pattern attributes for older browsers, but does not get in the way of these attributes in the case of newer browsers. There are several jQuery plugins which provide partial support for the HTML5 validation attributes including: · jQuery Validation — http://docs.jquery.com/Plugins/Validation · html5Form — http://www.matiasmancini.com.ar/jquery-plugin-ajax-form-validation-html5.html · h5Validate — http://ericleads.com/h5validate/ The jQuery Validation plugin – the most popular JavaScript validation library – supports the HTML5 required attribute, but it does not support the HTML5 pattern attribute. Likewise, the html5Form plugin does not support the pattern attribute. The h5Validate plugin provides the best support for the HTML5 validation attributes. The following page illustrates how this plugin supports both the required and pattern attributes: <!DOCTYPE html> <html xmlns="http://www.w3.org/1999/xhtml"> <head> <title>h5Validate</title> <style type="text/css"> .validationError { border: solid 2px red; } .validationValid { border: solid 2px green; } </style> </head> <body> <form id="customerForm"> <label> First Name: <input id="firstName" required /> </label> <label> Social Security Number: <input id="ssn" required pattern="^\d{3}-\d{2}-\d{4}$" title="Expected pattern is ###-##-####" /> </label> <input type="submit" /> </form> <script type="text/javascript" src="Scripts/jquery-1.4.4.min.js"></script> <script type="text/javascript" src="Scripts/jquery.h5validate.js"></script> <script type="text/javascript"> // Enable h5Validate plugin $("#customerForm").h5Validate({ errorClass: "validationError", validClass: "validationValid" }); // Prevent form submission when errors $("#customerForm").submit(function (evt) { if ($("#customerForm").h5Validate("allValid") === false) { evt.preventDefault(); } }); </script> </body> </html> When an input field fails validation, the validationError CSS class is applied to the field and the field appears with a red border. When an input field passes validation, the validationValid CSS class is applied to the field and the field appears with a green border. From the perspective of HTML5 validation, the h5Validate plugin is the best of the plugins. It adds support for the required and pattern attributes to browsers which do not natively support these attributes such as IE9. However, this plugin does not include everything in my wish list for a perfect HTML5 validation plugin. Here’s my wish list for the perfect back compat HTML5 validation plugin: 1. The plugin would disable itself when used with a browser which natively supports HTML5 validation attributes. The plugin should not be too greedy – it should not handle validation when a browser could do the work itself. 2. The plugin should simulate the same user interface for displaying validation error messages as the user interface displayed by browsers which natively support HTML5 validation. Chrome, Firefox, and Internet Explorer all display validation errors in a popup. The perfect plugin would also display a popup. 3. Finally, the plugin would add support for the setCustomValidity() method and the other methods of the HTML5 validation constraint API. That way, you could implement custom validation in a standards compatible way and you would know that it worked across all browsers both old and new. Security It would be irresponsible of me to end this blog post without mentioning the issue of security. It is important to remember that any client-side validation — including HTML5 validation — can be bypassed. You should use client-side validation with the intention to create a better user experience. Client validation is great for providing a user with immediate feedback when the user is in the process of completing a form. However, client-side validation cannot prevent an evil hacker from submitting unexpected form data to your web server. You should always enforce your validation rules on the server. The only way to ensure that a required field has a value is to verify that the required field has a value on the server. The HTML5 required attribute does not guarantee anything. Summary The goal of this blog post was to describe the support for validation contained in the HTML5 standard. You learned how to use both the required and the pattern attributes in an HTML5 form. We also discussed how you can implement custom validation by taking advantage of the setCustomValidity() method. Finally, I discussed the available jQuery plugins for adding support for the HTM5 validation attributes to older browsers. Unfortunately, I am unaware of any jQuery plugin which provides a perfect solution to the problem of backwards compatibility.

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• Going Paperless

  - by Jesse

  One year ago I came to work for a company where the entire development team is 100% “remote”; we’re spread over 3 time zones and each of us works from home. This seems to be an increasingly popular way for people to work and there are many articles and blog posts out there enumerating the advantages and disadvantages of working this way. I had read a lot about telecommuting before accepting this job and felt as if I had a pretty decent idea of what I was getting into, but I’ve encountered a few things over the past year that I did not expect. Among the most surprising by-products of working from home for me has been a dramatic reduction in the amount of paper that I use on a weekly basis. Hoarding In The Workplace Prior to my current telecommute job I worked in what most would consider pretty traditional office environments. I sat in cubicles furnished with an enormous plastic(ish) modular desks, had a mediocre (at best) PC workstation, and had ready access to a seemingly endless supply of legal pads, pens, staplers and paper clips. The ready access to paper, countless conference room meetings, and abundance of available surface area on my desk and in drawers created a perfect storm for wasting paper. I brought a pad of paper with me to every meeting I ever attended, scrawled some brief notes, and then tore that sheet off to keep next to my keyboard to follow up on any needed action items. Once my immediate need for the notes was fulfilled, that sheet would get shuffled off into a corner of my desk or filed away in a drawer “just in case”. I would guess that for all of the notes that I ever filed away, I might have actually had to dig up and refer to 2% of them (and that’s probably being very generous). That said, on those rare occasions that I did have to dig something up from old notes, it was usually pretty important and I ended up being very glad that I saved them. It was only when I would leave a job or move desks that I would finally gather all those notes together and take them to shredding bin to be disposed of. When I left my last job the amount of paper I had accumulated over my three years there was absurd, and I knew coworkers who had substance-abuse caliber paper wasting addictions that made my bad habit look like nail-biting in comparison. A Product Of My Environment I always hated using all of this paper, but simply couldn’t bring myself to stop. It would look bad if I showed up to an important conference room meeting without a pad of paper. What if someone said something profound! Plus, everyone else always brought paper with them. If you saw someone walking down the hallway with a pad of paper in hand you knew they must be on their way to a conference room meeting. Some people even had fancy looking portfolio notebook sheaths that gave their legal pads all the prestige of a briefcase. No one ever worried about running out of fresh paper because there was an endless supply, and there certainly was no shortage of places to store and file used paper. In short, the traditional office was setup for using tons and tons of paper; it’s baked into the culture there. For that reason, it didn’t take long for me to kick the paper habit once I started working from home. In my home office, desk and drawer space are at a premium. I don’t have the budget (or the tolerance) for huge modular office furniture in my spare bedroom. I also no longer have access to a bottomless pit of office supplies stock piled in cabinets and closets. If I want to use some paper, I have to go out and buy it. Finally (and most importantly), all of the meetings that I have to attend these days are “virtual”. We use instant messaging, VOIP, video conferencing, and e-mail to communicate with each other. All I need to take notes during a meeting is my computer, which I happen to be sitting right in front of all day. I don’t have any hard numbers for this, but my gut feeling is that I actually take a lot more notes now than I ever did when I worked in an office. The big difference is I don’t have to use any paper to do so. This makes it far easier to keep important information safe and organized. The Right Tool For The Job When I first started working from home I tried to find a single application that would fill the gap left by the pen and paper that I always had at my desk when I worked in an office. Well, there are no silver bullets and I’ve evolved my approach over time to try and find the best tool for the job at hand. Here’s a quick summary of how I take notes and keep everything organized. Notepad++ – This is the first application I turn to when I feel like there’s some bit of information that I need to write down and save. I use Launchy, so opening Notepad++ and creating a new file only takes a few keystrokes. If I find that the information I’m trying to get down requires a more sophisticated application I escalate as needed. The Desktop – By default, I save every file or other bit of information to the desktop. Anyone who has ever had to fix their parents computer before knows that this is a dangerous game (any file my mother has ever worked on is saved directly to the desktop and rarely moves anywhere else). I agree that storing things on the desktop isn’t a great long term approach to keeping organized, which is why I treat my desktop a bit like my e-mail inbox. I strive to keep both empty (or as close to empty as I possibly can). If something is on my desktop, it means that it’s something relevant to a task or project that I’m currently working on. About once a week I take things that I’m not longer working on and put them into my ‘Notes’ folder. The ‘Notes’ Folder – As I work on a task, I tend to accumulate multiple files associated with that task. For example, I might have a bit of SQL that I’m working on to gather data for a new report, a quick C# method that I came up with but am not yet ready to commit to source control, a bulleted list of to-do items in a .txt file, etc. If the desktop starts to get too cluttered, I create a new sub-folder in my ‘Notes’ folder. Each sub-folder’s name is the current date followed by a brief description of the task or project. Then all files related to that task or project go into that sub folder. By using the date as the first part of the folder name, these folders are automatically sorted in reverse chronological order. This means that things I worked on recently will generally be near the top of the list. Using the built-in Windows search functionality I now have a pretty quick and easy way to try and find something that I worked on a week ago or six months ago. Dropbox – Dropbox is a free service that lets you store up to 2GB of files “in the cloud” and have those files synced to all of the different computers that you use. My ‘Notes’ folder lives in Dropbox, meaning that it’s contents are constantly backed up and are always available to me regardless of which computer I’m using. They also have a pretty decent iPhone application that lets you browse and view all of the files that you have stored there. The free 2GB edition is probably enough for just storing notes, but I also pay $99/year for the 50GB storage upgrade and keep all of my music, e-books, pictures, and documents in Dropbox. It’s a fantastic service and I highly recommend it. Evernote – I use Evernote mostly to organize information that I access on a fairly regular basis. For example, my Evernote account has a running grocery shopping list, recipes that my wife and I use a lot, and contact information for people I contact infrequently enough that I don’t want to keep them in my phone. I know some people that keep nearly everything in Evernote, but there’s something about it that I find a bit clunky, so I tend to use it sparingly. Google Tasks – One of my biggest paper wasting habits was keeping a running task-list next to my computer at work. Every morning I would sit down, look at my task list, cross off what was done and add new tasks that I thought of during my morning commute. This usually resulted in having to re-copy the task list onto a fresh sheet of paper when I was done. I still keep a running task list at my desk, but I’ve started using Google Tasks instead. This is a dead-simple web-based application for quickly adding, deleting, and organizing tasks in a simple checklist style. You can quickly move tasks up and down on the list (which I use for prioritizing), and even create sub-tasks for breaking down larger tasks into smaller pieces. Balsamiq Mockups – This is a simple and lightweight tool for creating drawings of user interfaces. It’s great for sketching out a new feature, brainstorm the layout of a interface, or even draw up a quick sequence diagram. I’m terrible at drawing, so Balsamiq Mockups not only lets me create sketches that other people can actually understand, but it’s also handy because you can upload a sketch to a common location for other team members to access. I can honestly say that using these tools (and having limited resources at home) have lead me to cut my paper usage down to virtually none. If I ever were to return to a traditional office workplace (hopefully never!) I’d try to employ as many of these applications and techniques as I could to keep paper usage low. I feel far less cluttered and far better organized now.

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• HTTP error code 405: tomcat Url mapping issue

  - by Andrew

  I am having trouble POSTing to my java HTTPServlet. I am getting "HTTP Status 405 - HTTP method GET is not supported by this URL" from my tomcat server". When I debug the servlet the login method is never called. I think it's a url mapping issue within tomcat... web.xml <servlet-mapping> <servlet-name>faxcom</servlet-name> <url-pattern>/faxcom/*</url-pattern> </servlet-mapping> FaxcomService.java @Path("/rest") public class FaxcomService extends HttpServlet{ private FAXCOM_x0020_ServiceLocator service; private FAXCOM_x0020_ServiceSoap port; @GET @Produces("application/json") public String testGet() { return "{ \"got here\":true }"; } @POST @Path("/login") @Consumes("application/json") // @Produces("application/json") public Response login(LoginBean login) { ArrayList<ResultMessageBean> rm = new ArrayList<ResultMessageBean>(10); try { service = new FAXCOM_x0020_ServiceLocator(); service.setFAXCOM_x0020_ServiceSoapEndpointAddress("http://cd-faxserver/faxcom_ws/faxcomservice.asmx"); service.setMaintainSession(true); // enable sessions support port = service.getFAXCOM_x0020_ServiceSoap(); rm.add(new ResultMessageBean(port.logOn( "\\\\CD-Faxserver\\FaxcomQ_API", /* path to the queue */ login.getUserName(), /* username */ login.getPassword(), /* password */ login.getUserType() /* 2 = user conf user */ ))); } catch (RemoteException e) { e.printStackTrace(); } catch (ServiceException e) { e.printStackTrace(); } // return rm; return Response.status(201).entity(rm).build(); } @POST @Path("/newFaxMessage") @Consumes(MediaType.APPLICATION_JSON) @Produces(MediaType.APPLICATION_JSON) public ArrayList<ResultMessageBean> newFaxMessage(FaxBean fax) { ArrayList<ResultMessageBean> rm = new ArrayList<ResultMessageBean>(); try { rm.add(new ResultMessageBean(port.newFaxMessage( fax.getPriority(), /* priority: 0 - low, 1 - normal, 2 - high, 3 - urgent */ fax.getSendTime(), /* send time */ /* "0.0" - immediate */ /* "1.0" - offpeak */ /* "9/14/2007 5:12:11 PM" - to set specific time */ fax.getResolution(), /* resolution: 0 - low res, 1 - high res */ fax.getSubject(), /* subject */ fax.getCoverpage(), /* cover page: "" – default, “(none)� – no cover page */ fax.getMemo(), /* memo */ fax.getSenderName(), /* sender's name */ fax.getSenderFaxNumber(), /* sender's fax */ fax.getRecipients().get(0).getName(), /* recipient's name */ fax.getRecipients().get(0).getCompany(), /* recipient's company */ fax.getRecipients().get(0).getFaxNumber(), /* destination fax number */ fax.getRecipients().get(0).getVoiceNumber(), /* recipient's phone number */ fax.getRecipients().get(0).getAccountNumber() /* recipient's account number */ ))); if (fax.getRecipients().size() > 1) { for (int i = 1; i < fax.getRecipients().size(); i++) rm.addAll(addRecipient(fax.getRecipients().get(i))); } } catch (RemoteException e) { // TODO Auto-generated catch block e.printStackTrace(); } return rm; } } Main.java private static void main(String[] args) { try { URL url = new URL("https://andrew-vm/faxcom/rest/login"); HttpURLConnection conn = (HttpURLConnection) url.openConnection(); conn.setRequestMethod("POST"); conn.setDoOutput(true); conn.setRequestProperty("Content-Type", "application/json"); FileInputStream jsonDemo = new FileInputStream("login.txt"); OutputStream os = (OutputStream) conn.getOutputStream(); os.write(IOUtils.toByteArray(jsonDemo)); os.flush(); if (conn.getResponseCode() != 200) { throw new RuntimeException("Failed : HTTP error code : " + conn.getResponseCode()); } BufferedReader br = new BufferedReader(new InputStreamReader( (conn.getInputStream()))); String output; System.out.println("Output from Server .... \n"); while ((output = br.readLine()) != null) { System.out.println(output); } // Don't want to disconnect - servletInstance will be destroyed // conn.disconnect(); } catch (MalformedURLException e) { e.printStackTrace(); } catch (IOException e) { e.printStackTrace(); } } I am working from this tutorial: http://www.mkyong.com/webservices/jax-rs/restfull-java-client-with-java-net-url/

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• SATA errors reported during boot: exception Emask 0x40 SAct 0x0 SErr 0x80800 action 0x0

  - by digby280

  I have noticed some error during the Linux boot. They seem to continue to occur after the boot adding lines to the log every few seconds. Once booted this normally does not appear to be causing any problems. However, around 1 in 10 boots results in a kernel panic and the computer has on two or three occasions suddenly rebooted after being powered on for a number of hours. I presume the cause of the reboot is a kernel panic as well. I am running Ubuntu 11.10 and I have had Ubuntu installed on the computer for around a year. I have googled around and not found anything useful. I have provided the kernel log lines and the output of smartctl. Can anyone explain exactly what these errors mean, or better still how to resolve them? Apr 2 16:51:27 dell580 kernel: [ 19.831140] EXT4-fs (sdb2): re-mounted. Opts: errors=remount-ro,user_xattr,commit=0 Apr 2 16:51:27 dell580 kernel: [ 19.934194] tg3 0000:03:00.0: eth0: Link is down Apr 2 16:51:28 dell580 kernel: [ 20.929468] tg3 0000:03:00.0: eth0: Link is up at 100 Mbps, full duplex Apr 2 16:51:28 dell580 kernel: [ 20.929471] tg3 0000:03:00.0: eth0: Flow control is on for TX and on for RX Apr 2 16:51:28 dell580 kernel: [ 20.929727] ADDRCONF(NETDEV_CHANGE): eth0: link becomes ready Apr 2 16:51:29 dell580 kernel: [ 21.609381] EXT4-fs (sdb2): re-mounted. Opts: errors=remount-ro,user_xattr,commit=0 Apr 2 16:51:29 dell580 kernel: [ 21.616515] ata2.01: exception Emask 0x40 SAct 0x0 SErr 0x80800 action 0x0 Apr 2 16:51:29 dell580 kernel: [ 21.616519] ata2.01: SError: { HostInt 10B8B } Apr 2 16:51:29 dell580 kernel: [ 21.616525] ata2.00: hard resetting link Apr 2 16:51:29 dell580 kernel: [ 21.934036] ata2.01: hard resetting link Apr 2 16:51:29 dell580 kernel: [ 22.408890] ata2.00: SATA link up 1.5 Gbps (SStatus 113 SControl 300) Apr 2 16:51:29 dell580 kernel: [ 22.408907] ata2.01: SATA link up 3.0 Gbps (SStatus 123 SControl 300) Apr 2 16:51:29 dell580 kernel: [ 22.440934] ata2.00: configured for UDMA/100 Apr 2 16:51:29 dell580 kernel: [ 22.449040] ata2.01: configured for UDMA/133 Apr 2 16:51:29 dell580 kernel: [ 22.449818] ata2: EH complete Apr 2 16:51:33 dell580 kernel: [ 26.122664] ata2.01: exception Emask 0x40 SAct 0x0 SErr 0x80800 action 0x0 Apr 2 16:51:33 dell580 kernel: [ 26.122670] ata2.01: SError: { HostInt 10B8B } Apr 2 16:51:33 dell580 kernel: [ 26.122677] ata2.00: hard resetting link Apr 2 16:51:33 dell580 kernel: [ 26.442684] ata2.01: hard resetting link Apr 2 16:51:34 dell580 kernel: [ 26.925545] ata2.00: SATA link up 1.5 Gbps (SStatus 113 SControl 300) Apr 2 16:51:34 dell580 kernel: [ 26.925561] ata2.01: SATA link up 3.0 Gbps (SStatus 123 SControl 300) Apr 2 16:51:34 dell580 kernel: [ 26.961542] ata2.00: configured for UDMA/100 Apr 2 16:51:34 dell580 kernel: [ 26.969616] ata2.01: configured for UDMA/133 Apr 2 16:51:34 dell580 kernel: [ 26.970400] ata2: EH complete Apr 2 16:51:35 dell580 kernel: [ 28.111180] ata2.01: exception Emask 0x40 SAct 0x0 SErr 0x80800 action 0x0 Apr 2 16:51:35 dell580 kernel: [ 28.111184] ata2.01: SError: { HostInt 10B8B } Apr 2 16:51:35 dell580 kernel: [ 28.111191] ata2.00: hard resetting link Apr 2 16:51:35 dell580 kernel: [ 28.429674] ata2.01: hard resetting link Apr 2 16:51:36 dell580 kernel: [ 28.904557] ata2.00: SATA link up 1.5 Gbps (SStatus 113 SControl 300) Apr 2 16:51:36 dell580 kernel: [ 28.904572] ata2.01: SATA link up 3.0 Gbps (SStatus 123 SControl 300) Apr 2 16:51:36 dell580 kernel: [ 28.936609] ata2.00: configured for UDMA/100 Apr 2 16:51:36 dell580 kernel: [ 28.944692] ata2.01: configured for UDMA/133 Apr 2 16:51:36 dell580 kernel: [ 28.945464] ata2: EH complete Apr 2 16:51:38 dell580 kernel: [ 31.581756] eth0: no IPv6 routers present Apr 2 16:51:38 dell580 kernel: [ 32.103066] ata2.01: exception Emask 0x40 SAct 0x0 SErr 0x80800 action 0x0 Apr 2 16:51:38 dell580 kernel: [ 32.103074] ata2.01: SError: { HostInt 10B8B } Apr 2 16:51:38 dell580 kernel: [ 32.103085] ata2.00: hard resetting link Apr 2 16:51:38 dell580 kernel: [ 32.419669] ata2.01: hard resetting link Apr 2 16:51:39 dell580 kernel: [ 32.894518] ata2.00: SATA link up 1.5 Gbps (SStatus 113 SControl 300) Apr 2 16:51:39 dell580 kernel: [ 32.894533] ata2.01: SATA link up 3.0 Gbps (SStatus 123 SControl 300) Apr 2 16:51:39 dell580 kernel: [ 32.926536] ata2.00: configured for UDMA/100 Apr 2 16:51:39 dell580 kernel: [ 32.934715] ata2.01: configured for UDMA/133 Apr 2 16:51:39 dell580 kernel: [ 32.935578] ata2: EH complete Here's the output of smartctl for the drive. smartctl 5.41 2011-06-09 r3365 [x86_64-linux-3.0.0-17-generic] (local build) Copyright (C) 2002-11 by Bruce Allen, http://smartmontools.sourceforge.net === START OF INFORMATION SECTION === Model Family: SAMSUNG SpinPoint F1 DT Device Model: SAMSUNG HD103UJ Serial Number: S13PJ90QC19706 LU WWN Device Id: 5 0000f0 00b1c7960 Firmware Version: 1AA01113 User Capacity: 1,000,204,886,016 bytes [1.00 TB] Sector Size: 512 bytes logical/physical Device is: In smartctl database [for details use: -P show] ATA Version is: 8 ATA Standard is: ATA-8-ACS revision 3b Local Time is: Mon Apr 2 17:13:48 2012 BST SMART support is: Available - device has SMART capability. SMART support is: Enabled === START OF READ SMART DATA SECTION === SMART overall-health self-assessment test result: PASSED General SMART Values: Offline data collection status: (0x00) Offline data collection activity was never started. Auto Offline Data Collection: Disabled. Self-test execution status: ( 41) The self-test routine was interrupted by the host with a hard or soft reset. Total time to complete Offline data collection: (11772) seconds. Offline data collection capabilities: (0x7b) SMART execute Offline immediate. Auto Offline data collection on/off support. Suspend Offline collection upon new command. Offline surface scan supported. Self-test supported. Conveyance Self-test supported. Selective Self-test supported. SMART capabilities: (0x0003) Saves SMART data before entering power-saving mode. Supports SMART auto save timer. Error logging capability: (0x01) Error logging supported. General Purpose Logging supported. Short self-test routine recommended polling time: ( 2) minutes. Extended self-test routine recommended polling time: ( 197) minutes. Conveyance self-test routine recommended polling time: ( 21) minutes. SCT capabilities: (0x003f) SCT Status supported. SCT Error Recovery Control supported. SCT Feature Control supported. SCT Data Table supported. SMART Attributes Data Structure revision number: 16 Vendor Specific SMART Attributes with Thresholds: ID# ATTRIBUTE_NAME FLAG VALUE WORST THRESH TYPE UPDATED WHEN_FAILED RAW_VALUE 1 Raw_Read_Error_Rate 0x000f 100 100 051 Pre-fail Always - 0 3 Spin_Up_Time 0x0007 076 076 011 Pre-fail Always - 7940 4 Start_Stop_Count 0x0032 099 099 000 Old_age Always - 521 5 Reallocated_Sector_Ct 0x0033 100 100 010 Pre-fail Always - 0 7 Seek_Error_Rate 0x000f 253 253 051 Pre-fail Always - 0 8 Seek_Time_Performance 0x0025 100 100 015 Pre-fail Offline - 0 9 Power_On_Hours 0x0032 100 100 000 Old_age Always - 642 10 Spin_Retry_Count 0x0033 100 100 051 Pre-fail Always - 0 11 Calibration_Retry_Count 0x0012 100 100 000 Old_age Always - 0 12 Power_Cycle_Count 0x0032 100 100 000 Old_age Always - 482 13 Read_Soft_Error_Rate 0x000e 100 100 000 Old_age Always - 0 183 Runtime_Bad_Block 0x0032 100 100 000 Old_age Always - 759 184 End-to-End_Error 0x0033 100 100 000 Pre-fail Always - 0 187 Reported_Uncorrect 0x0032 100 100 000 Old_age Always - 0 188 Command_Timeout 0x0032 100 100 000 Old_age Always - 0 190 Airflow_Temperature_Cel 0x0022 073 069 000 Old_age Always - 27 (Min/Max 16/27) 194 Temperature_Celsius 0x0022 073 067 000 Old_age Always - 27 (Min/Max 16/28) 195 Hardware_ECC_Recovered 0x001a 100 100 000 Old_age Always - 320028 196 Reallocated_Event_Count 0x0032 100 100 000 Old_age Always - 0 197 Current_Pending_Sector 0x0012 100 100 000 Old_age Always - 0 198 Offline_Uncorrectable 0x0030 100 100 000 Old_age Offline - 0 199 UDMA_CRC_Error_Count 0x003e 099 099 000 Old_age Always - 1494 200 Multi_Zone_Error_Rate 0x000a 100 100 000 Old_age Always - 0 201 Soft_Read_Error_Rate 0x000a 253 253 000 Old_age Always - 0 SMART Error Log Version: 1 ATA Error Count: 211 (device log contains only the most recent five errors) CR = Command Register [HEX] FR = Features Register [HEX] SC = Sector Count Register [HEX] SN = Sector Number Register [HEX] CL = Cylinder Low Register [HEX] CH = Cylinder High Register [HEX] DH = Device/Head Register [HEX] DC = Device Command Register [HEX] ER = Error register [HEX] ST = Status register [HEX] Powered_Up_Time is measured from power on, and printed as DDd+hh:mm:SS.sss where DD=days, hh=hours, mm=minutes, SS=sec, and sss=millisec. It "wraps" after 49.710 days. Error 211 occurred at disk power-on lifetime: 0 hours (0 days + 0 hours) When the command that caused the error occurred, the device was active or idle. After command completion occurred, registers were: ER ST SC SN CL CH DH -- -- -- -- -- -- -- 84 51 0f 31 63 8f e1 Error: ICRC, ABRT 15 sectors at LBA = 0x018f6331 = 26174257 Commands leading to the command that caused the error were: CR FR SC SN CL CH DH DC Powered_Up_Time Command/Feature_Name -- -- -- -- -- -- -- -- ---------------- -------------------- c8 00 00 40 62 8f e1 08 00:01:00.460 READ DMA c8 00 20 00 7c 30 e0 08 00:01:00.450 READ DMA c8 00 00 10 49 8f e1 08 00:01:00.440 READ DMA c8 00 e0 20 d0 30 e0 08 00:01:00.420 READ DMA c8 00 00 c0 59 90 e1 08 00:01:00.400 READ DMA Error 210 occurred at disk power-on lifetime: 0 hours (0 days + 0 hours) When the command that caused the error occurred, the device was active or idle. After command completion occurred, registers were: ER ST SC SN CL CH DH -- -- -- -- -- -- -- 84 51 cf e9 cf 66 e0 Error: ICRC, ABRT 207 sectors at LBA = 0x0066cfe9 = 6737897 Commands leading to the command that caused the error were: CR FR SC SN CL CH DH DC Powered_Up_Time Command/Feature_Name -- -- -- -- -- -- -- -- ---------------- -------------------- c8 00 00 b8 cf 66 e0 08 00:08:29.780 READ DMA c8 00 60 60 c9 18 e0 08 00:08:29.770 READ DMA c8 00 40 20 c9 18 e0 08 00:08:29.770 READ DMA c8 00 20 00 c9 18 e0 08 00:08:29.760 READ DMA c8 00 20 98 cf 66 e0 08 00:08:29.750 READ DMA Error 209 occurred at disk power-on lifetime: 0 hours (0 days + 0 hours) When the command that caused the error occurred, the device was active or idle. After command completion occurred, registers were: ER ST SC SN CL CH DH -- -- -- -- -- -- -- 84 51 2f d1 74 e0 e0 Error: ICRC, ABRT 47 sectors at LBA = 0x00e074d1 = 14709969 Commands leading to the command that caused the error were: CR FR SC SN CL CH DH DC Powered_Up_Time Command/Feature_Name -- -- -- -- -- -- -- -- ---------------- -------------------- c8 00 00 00 74 e0 e0 08 00:00:30.940 READ DMA c8 00 20 18 36 de e0 08 00:00:30.930 READ DMA c8 00 08 48 f1 dd e0 08 00:00:30.930 READ DMA c8 00 08 a8 f0 dd e0 08 00:00:30.930 READ DMA c8 00 08 90 f0 dd e0 08 00:00:30.930 READ DMA Error 208 occurred at disk power-on lifetime: 0 hours (0 days + 0 hours) When the command that caused the error occurred, the device was active or idle. After command completion occurred, registers were: ER ST SC SN CL CH DH -- -- -- -- -- -- -- 84 51 7f 21 88 9d e0 Error: ICRC, ABRT 127 sectors at LBA = 0x009d8821 = 10324001 Commands leading to the command that caused the error were: CR FR SC SN CL CH DH DC Powered_Up_Time Command/Feature_Name -- -- -- -- -- -- -- -- ---------------- -------------------- c8 00 a0 00 88 9d e0 08 00:00:27.610 READ DMA c8 00 58 a8 e7 9c e0 08 00:00:27.610 READ DMA c8 00 00 28 e6 9c e0 08 00:00:27.610 READ DMA c8 00 00 e0 e4 9c e0 08 00:00:27.610 READ DMA c8 00 00 90 e0 9c e0 08 00:00:27.600 READ DMA Error 207 occurred at disk power-on lifetime: 0 hours (0 days + 0 hours) When the command that caused the error occurred, the device was active or idle. After command completion occurred, registers were: ER ST SC SN CL CH DH -- -- -- -- -- -- -- 04 51 26 6a 6a c3 e0 Error: ABRT at LBA = 0x00c36a6a = 12806762 Commands leading to the command that caused the error were: CR FR SC SN CL CH DH DC Powered_Up_Time Command/Feature_Name -- -- -- -- -- -- -- -- ---------------- -------------------- ca 00 00 90 69 c3 e0 08 00:29:39.350 WRITE DMA ca 00 40 90 68 c3 e0 08 00:29:39.350 WRITE DMA ca 00 40 50 65 c3 e0 08 00:29:39.350 WRITE DMA ca 00 40 d0 64 c3 e0 08 00:29:39.350 WRITE DMA ca 00 40 90 63 c3 e0 08 00:29:39.350 WRITE DMA SMART Self-test log structure revision number 1 Num Test_Description Status Remaining LifeTime(hours) LBA_of_first_error # 1 Short offline Interrupted (host reset) 90% 638 - # 2 Short offline Interrupted (host reset) 90% 638 - # 3 Extended offline Interrupted (host reset) 90% 638 - # 4 Short offline Interrupted (host reset) 90% 638 - # 5 Extended offline Interrupted (host reset) 90% 638 - SMART Selective self-test log data structure revision number 1 SPAN MIN_LBA MAX_LBA CURRENT_TEST_STATUS 1 0 0 Not_testing 2 0 0 Not_testing 3 0 0 Not_testing 4 0 0 Not_testing 5 0 0 Not_testing Selective self-test flags (0x0): After scanning selected spans, do NOT read-scan remainder of disk. If Selective self-test is pending on power-up, resume after 0 minute delay.

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• claimsResponse Always Return Null

  - by Chirag Pandya

  hello i have a following code in asp.net. i have used DotNetOpenAuth.dll for openID. the code is under protected void openidValidator_ServerValidate(object source, ServerValidateEventArgs args) { // This catches common typos that result in an invalid OpenID Identifier. args.IsValid = Identifier.IsValid(args.Value); } protected void loginButton_Click(object sender, EventArgs e) { if (!this.Page.IsValid) { return; // don't login if custom validation failed. } try { using (OpenIdRelyingParty openid = this.createRelyingParty()) { IAuthenticationRequest request = openid.CreateRequest(this.openIdBox.Text); // This is where you would add any OpenID extensions you wanted // to include in the authentication request. ClaimsRequest objClmRequest = new ClaimsRequest(); objClmRequest.Email = DemandLevel.Request; objClmRequest.Country = DemandLevel.Request; request.AddExtension(objClmRequest); // Send your visitor to their Provider for authentication. request.RedirectToProvider(); } } catch (ProtocolException ex) { this.openidValidator.Text = ex.Message; this.openidValidator.IsValid = false; } } protected void Page_Load(object sender, EventArgs e) { this.openIdBox.Focus(); if (Request.QueryString["clearAssociations"] == "1") { Application.Remove("DotNetOpenAuth.OpenId.RelyingParty.OpenIdRelyingParty.ApplicationStore"); UriBuilder builder = new UriBuilder(Request.Url); builder.Query = null; Response.Redirect(builder.Uri.AbsoluteUri); } OpenIdRelyingParty openid = this.createRelyingParty(); var response = openid.GetResponse(); if (response != null) { switch (response.Status) { case AuthenticationStatus.Authenticated: // This is where you would look for any OpenID extension responses included // in the authentication assertion. var claimsResponse = response.GetExtension<ClaimsResponse>(); State.ProfileFields = claimsResponse; // Store off the "friendly" username to display -- NOT for username lookup State.FriendlyLoginName = response.FriendlyIdentifierForDisplay; // Use FormsAuthentication to tell ASP.NET that the user is now logged in, // with the OpenID Claimed Identifier as their username. FormsAuthentication.RedirectFromLoginPage(response.ClaimedIdentifier, false); break; case AuthenticationStatus.Canceled: this.loginCanceledLabel.Visible = true; break; case AuthenticationStatus.Failed: this.loginFailedLabel.Visible = true; break; // We don't need to handle SetupRequired because we're not setting // IAuthenticationRequest.Mode to immediate mode. ////case AuthenticationStatus.SetupRequired: //// break; } } } private OpenIdRelyingParty createRelyingParty() { OpenIdRelyingParty openid = new OpenIdRelyingParty(); int minsha, maxsha, minversion; if (int.TryParse(Request.QueryString["minsha"], out minsha)) { openid.SecuritySettings.MinimumHashBitLength = minsha; } if (int.TryParse(Request.QueryString["maxsha"], out maxsha)) { openid.SecuritySettings.MaximumHashBitLength = maxsha; } if (int.TryParse(Request.QueryString["minversion"], out minversion)) { switch (minversion) { case 1: openid.SecuritySettings.MinimumRequiredOpenIdVersion = ProtocolVersion.V10; break; case 2: openid.SecuritySettings.MinimumRequiredOpenIdVersion = ProtocolVersion.V20; break; default: throw new ArgumentOutOfRangeException("minversion"); } } return openid; } for above code i am always getting var claimsResponse = response.GetExtension<ClaimsResponse>(); i am always getting claimsResponse= null. what is the reason why it happen. is there any requirement which is required for openid like domain validation for RelyingParty?? please give me answer as soon as possible.

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• Allocation algorithm help, using Python.

  - by Az

  Hi there, I've been working on this general allocation algorithm for students. The pseudocode for it (a Python implementation) is: for a student in a dictionary of students: for student's preference in a set of preferences (ordered from 1 to 10): let temp_project be the first preferred project check if temp_project is available if so, allocate it to them and make the project UNavailable to others Quite simply this will try to allocate projects by starting from their most preferred. The way it works, out of a set of say 100 projects, you list 10 you would want to do. So the 10th project wouldn't be the "least preferred overall" but rather the least preferred in their chosen set, which isn't so bad. Obviously if it can't allocate a project, a student just reverts to the base case which is an allocation of None, with a rank of 11. What I'm doing is calculating the allocation "quality" based on a weighted sum of the ranks. So the lower the numbers (i.e. more highly preferred projects), the better the allocation quality (i.e. more students have highly preferred projects). That's basically what I've currently got. Simple and it works. Now I'm working on this algorithm that tries to minimise the allocation weight locally (this pseudocode is a bit messy, sorry). The only reason this will probably work is because my "search space" as it is, isn't particularly large (just a very general, anecdotal observation, mind you). Since the project is only specific to my Department, we have their own limits imposed. So the number of students can't exceed 100 and the number of preferences won't exceed 10. for student in a dictionary/list/whatever of students: where i = 0 take the (i)st student, (i+1)nd student for their ranks: allocate the projects and set local_weighting to be sum(student_i.alloc_proj_rank, student_i+1.alloc_proj_rank) these are the cases: if local_weighting is 2 (i.e. both ranks are 1): then i += 1 and and continue above if local weighting is = N>2 (i.e. one or more ranks are greater than 1): let temp_local_weighting be N: pick student with lowest rank and then move him to his next rank and pick the other student and reallocate his project after this if temp_local_weighting is < N: then allocate those projects to the students move student with lowest rank to the next rank and reallocate other if temp_local_weighting < previous_temp_allocation: let these be the new allocated projects try moving for the lowest rank and reallocate other else: if this weighting => previous_weighting let these be the allocated projects i += 1 and move on for the rest of the students So, questions: This is sort of a modification of simulated annealing, but any sort of comments on this would be appreciated. How would I keep track of which student is (i) and which student is (i+1) If my overall list of students is 100, then the thing would mess up on (i+1) = 101 since there is none. How can I circumvent that? Any immediate flaws that can be spotted? Extra info: My students dictionary is designed as such: students[student_id] = Student(student_id, student_name, alloc_proj, alloc_proj_rank, preferences) where preferences is in the form of a dictionary such that preferences[rank] = {project_id}

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• Why does C# thread die?

  - by JackN

  This is my 1st C# project so I may be doing something obviously improper in the code below. I am using .NET, WinForms (I think), and this is a desktop application until I get the bugs out. UpdateGui() uses Invoke((MethodInvoker)delegate to update various GUI controls based on received serial data and sends a GetStatus() command out the serial port 4 times a second. Thread Read() reads the response from serial port whenever it arrives which should be near immediate. SerialPortFixer is a SerialPort IOException Workaround in C# I found at http://zachsaw.blogspot.com/2010/07/serialport-ioexception-workaround-in-c.html. After one or both threads die I'll see something like The thread 0x1288 has exited with code 0 (0x0). in the debug code output. Why do UpdateGui() and/or Read() eventually die? public partial class UpdateStatus : Form { private readonly byte[] Command = new byte[32]; private readonly byte[] Status = new byte[32]; readonly Thread readThread; private static readonly Mutex commandMutex = new Mutex(); private static readonly Mutex statusMutex = new Mutex(); ... public UpdateStatus() { InitializeComponent(); SerialPortFixer.Execute("COM2"); if (serialPort1.IsOpen) { serialPort1.Close(); } try { serialPort1.Open(); } catch (Exception e) { labelWarning.Text = LOST_COMMUNICATIONS + e; labelStatus.Text = LOST_COMMUNICATIONS + e; labelWarning.Visible = true; } readThread = new Thread(Read); readThread.Start(); new Timer(UpdateGui, null, 0, 250); } static void ProcessStatus(byte[] status) { Status.State = (State) status[4]; Status.Speed = status[6]; // MSB Status.Speed *= 256; Status.Speed += status[5]; var Speed = Status.Speed/GEAR_RATIO; Status.Speed = (int) Speed; ... } public void Read() { while (serialPort1 != null) { try { serialPort1.Read(Status, 0, 1); if (Status[0] != StartCharacter[0]) continue; serialPort1.Read(Status, 1, 1); if (Status[1] != StartCharacter[1]) continue; serialPort1.Read(Status, 2, 1); if (Status[2] != (int)Command.GetStatus) continue; serialPort1.Read(Status, 3, 1); ... statusMutex.WaitOne(); ProcessStatus(Status); Status.update = true; statusMutex.ReleaseMutex(); } catch (Exception e) { Console.WriteLine(@"ERROR! Read() " + e); } } } public void GetStatus() { const int parameterLength = 0; // For GetStatus statusMutex.WaitOne(); Status.update = false; statusMutex.ReleaseMutex(); commandMutex.WaitOne(); if (!SendCommand(Command.GetStatus, parameterLength)) { Console.WriteLine(@"ERROR! SendCommand(GetStatus)"); } commandMutex.ReleaseMutex(); } private void UpdateGui(object x) { try { Invoke((MethodInvoker)delegate { Text = DateTime.Now.ToLongTimeString(); statusMutex.WaitOne(); if (Status.update) { if (Status.Speed > progressBarSpeed.Maximum) { Status.Speed = progressBarSpeed.Maximum; } progressBarSpeed.Value = Status.Speed; labelSpeed.Text = Status.Speed + RPM; ... } else { labelWarning.Text = LOST_COMMUNICATIONS; labelStatus.Text = LOST_COMMUNICATIONS; labelWarning.Visible = true; } statusMutex.ReleaseMutex(); GetStatus(); }); } catch (Exception e) { Console.WriteLine(@"ERROR! UpdateGui() " + e); } } }

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• CodePlex Daily Summary for Thursday, November 03, 2011

  CodePlex Daily Summary for Thursday, November 03, 2011Popular ReleasesFlagConsole: 1.0.1: BUGFIXES: - Fixed a bug, which caused the label not to draw a word, if it had the same length as the label's length.Nearforums - ASP.NET MVC forum engine: Nearforums v7.0: Version 7.0 of Nearforums, the ASP.NET MVC Forum Engine, containing new features: UI: Flexible layout to handle both list and table-like template layouts. Theming - Visual choice of themes: Deliver some templates on installation, export/import functionality, preview. Allow site owners to choose default list sort order for the forums. Forum latest activity. Visit the project Roadmap for more details.?????????? - ????????: All-In-One Code Framework ??? 2011-11-02: http://download.codeplex.com/Project/Download/FileDownload.aspx?ProjectName=1codechs&DownloadId=216140 ??????，11??，?????20????Microsoft OneCode Sample，????6?Program Language Sample，2?Windows Base Sample，2?GDI+ Sample，4?Internet Explorer Sample?6?ASP.NET Sample。?????????????。 ????，?????。http://i3.codeplex.com/Project/Download/FileDownload.aspx?ProjectName=1code&DownloadId=128165 Program Language CSImageFullScreenSlideShow VBImageFullScreenSlideShow CSDynamicallyBuildLambdaExpressionWithFie...Python Tools for Visual Studio: 1.1 Alpha: We’re pleased to announce the release of Python Tools for Visual Studio 1.1 Alpha. Python Tools for Visual Studio (PTVS) is an open-source plug-in for Visual Studio which supports programming with the Python programming language. This release includes new core IDE features, a couple of new sample libraries for interacting with Kinect and Excel, and many bug fixes for issues reported since the release of 1.0. For the core IDE features we’ve added many new features which improve the basic edit...BExplorer (Better Explorer): Better Explorer 2.0.0.631 Alpha: Changelog: Added: Some new functions in ribbon Added: Possibility to choose displayed columns Added: Basic Search Fixed: Some bugs after navigation Fixed: Attempt to fix slow navigation and slow start Known issues: - BreadcrumbBar fails on some situations - Basic search not work quite well in some situations Please if anyone find bugs be kind and report them at the Issue Tracker! Thanks!DotNetNuke® Community Edition: 05.06.04: Major Highlights Fixed issue with upgrades on systems that had upgraded the Telerik library to 6.0.0 Fixed issue with Razor Host upgrade to 5.6.3 The logic for module administration checks contains incorrect logic in 1 place, opening the possibility of a user with edit permissions gaining access to functionality they should not have through a particularly crafted url Security FixesBrowsers support the ability to remember common strings such as usernames/addresses etc. Code was adde...Terminals: Version 2.0 - Beta 2 Release: The team has finally put the nail into the official release date for version 2.0. As bugs are winding down on the 2.0 Roadmap we decided to push out another build - the first 2.0 Beta build. Please take time to use and abuse this release. We left logging in place, and this is a debug build so be sure to submit your logs on each bug reported, and please do report all bugs! Check the source code page on the site, this beta includes all commits since (and including) the 90428 check-in back i...iTuner - The iTunes Companion: iTuner 1.4.4322: Added German (unverified, apologies if incorrect) Properly source invariant resources with correct resIDs Replaced obsolete lyric providers with working providers Fix Pseudolater to correctly morph every third char Fix null reference in CatalogBaseTrack Folder Changes: Track Folder Changes 1.0: Track Folder Changes 1.0 (binary)Devpad: 4.6: Whats new for Devpad 4.6: New Recent Files New Run in Safari Minor Bug Fix's, improvements and speed upsWindows Workflow Foundation on Codeplex: Microsoft.Activities v1.8.8: Microsoft.Activities Overview How do I install Microsoft.Activities? Updates in this release9318Technical Analysis Engine for .NET: Technical Analysis Engine 1.25: What's new in the 1.25 release (2011-11-01): - Added Williams %R indicator - Added Moving Average Envelopes indicatorBoxWorld: BoxWorld_2011.10.30: BoxWorld - 8.0.1110.30 This is the initial release of BoxWorld. I'd recommend downloading the installer as it contains the compiled code and everything all nicely contained. By default, you end up with this directory structure: C:\Program Files\ViperWorks\BoxWorld C:\Program Files\ViperWorks\BoxWorld\Data C:\Program Files\ViperWorks\BoxWorld\Interface C:\Program Files\ViperWorks\BoxWorld\Source In the root you have the compiled EXE files, one for the main release, one for the LITE release ...VidCoder: 1.2.1: Fixed a couple regressions: video encoder was blank in queue and crashes with the High Profile preset when opening the Settings window. Fixed problem with auto-update introduced in 1.2.0. If you have 1.2.0 you will need to update manually to get this.AssaultCube Reloaded: Release 2.3: THE RELEASE YOU'VE ALL BEEN WAITING FOR! IT CAN NOW BE CONSIDERED STABLE Linux has Debian 64-bit precompiled binaries, but you can compile your own as it also contains the source. If you are using Mac or other operating systems, download the Linux package. The server pack is ready for both Windows and Linux, but you might need to compile your own for linux (source included) If you are using Windows and require the source code, download the source package!A Microblog API (SINA weibo.com open API in C#, .Net???????API): AMicroblogAPI v1.0: AMicroBlogAPI is a C# implementation, a strong-typed deep encapsulation, a easy-to-use .net wrapper of SINA microblog API v1.0. App developers no longer need to parse various HTTP responses -- all responses are parsed into strong types; No longer need to construt the request query strings -- just simply gives the values of parameters; No longer need to implement the OAuth -- a single call could logs the user on. In this release (AMicroblogAPI v1.0), all basic data APIs are implemented. For ...patterns & practices: Enterprise Library Contrib: Enterprise Library Contrib - 5.0 (Oct 2011): This release of Enterprise Library Contrib is based on the Microsoft patterns & practices Enterprise Library 5.0 core and contains the following: Common extensionsTypeConfigurationElement<T> - A Polymorphic Configuration Element without having to be part of a PolymorphicConfigurationElementCollection. AnonymousConfigurationElement - A Configuration element that can be uniquely identified without having to define its name explicitly. Data Access Application Block extensionsMySql Provider - ...Network Monitor Open Source Parsers: Network Monitor Parsers 3.4.2748: The Network Monitor Parsers packages contain parsers for more than 400 network protocols, including RFC based public protocols and protocols for Microsoft products defined in the Microsoft Open Specifications for Windows and SQL Server. NetworkMonitor_Parsers.msi is the base parser package which defines parsers for commonly used public protocols and protocols for Microsoft Windows. In this release, NetowrkMonitor_Parsers.msi continues to improve quality and fix bugs. It has included the fo...Duckworth Lewis Professional Edition Calculator: DLcalc 3.0: DLcalc 3.0 can perform Duckworth/Lewis Professional Edition calculations 100% accurately. It also produces over-by-over and ball-by-ball PAR score tables.Media Companion: MC 3.420b Weekly: Ensure .NET 4.0 Full Framework is installed. (Available from http://www.microsoft.com/download/en/details.aspx?id=17718) Ensure the NFO ID fix is applied when transitioning from versions prior to 3.416b. (Details here) Movies Fixed: Fanart and poster scraping issues TV Shows (Re)Added: Rebuild single show Fixed: Issue when shows are moved from original location Ability to handle " for actor nicknames Crash when episode name contains "<" (does not scrape yet) Clears fanart when switch...New ProjectsASP.NET MVC fluent validation framework: FluentMvc allow you to create validatable models without using any validation attributes.BeanPermutator: The BeanPermutator library provides a robust permutations engine. It was designed with framework API, optimal performance, and memory usage in mind. For performance, the implementation is modeled after STL's next_permutation; except with added support for conditional result sets.Cicero: Cicero is a library/application to programmatically analyze managed crash dumps. It provides a managed API to load dumps and look at managed objects, using [url:SOS|http://msdn.microsoft.com/en-us/library/bb190764.aspx] under the covers.CodePlex Windows Phone App: This project deals with how to browse efficently through codeplex website using windows phone capabilities.Collage: A photo collage screensaver.Docs Professional Archiving System: This application basically provides a professional audit compliant archiving system with storage service.EBSCOLunch: This app simply shows ebsco's lunch menu. It runs in the system tray and when clicked on shows today's cafeteria specials.Emesary: C# Interobject communication and application mssaging: Simple quick and efficient class based interobject communcation to allow decoupled disparate parts of a system to function together without knowing about each, e.g GUI, DB and business logic.Enterprise Data Entry, Reporting and Analysis Tool: This project will have app with different modules that will show the interface tools functions based on the designation of an employee as defined in Active Directory. Example: A team manager can view all the details regarding his immediate subordinates. Financial date and time libary: Date and time routines that know about holidays, rolling conventions, and day count fractions.Frame Work Model by Patán: Proyecto de modelado de FrameworkIttxa: Is in Alpha releaseKooboo CMS data sync module: Kooboo cms data export / import module.MetroBlog: A Windows 8 Metro inspired blog. Mosque: In the name of GOD this is a portalMPO tools: A .net library for parsing .mpo stereo images (in Multi-Picture Format).mytest5: my testtttttttttNetflix MVP Example: Example .NET movie application using the MVP pattern with windows forms and WPF. Uses the Netflix Odata service to get movie information.OpenStreetMap2Oracle: OpenStreetMap2Oracle is a windows application, which exports OpenStreetMap Data (*.osm - files) in an oracle database. The geometries will be stored in oracle's SDO_GEOMETRY datatype. It is developed in C Sharp with modern WPF - UI. PSRR - Remote Registry PowerShell 3.0 Module: Remote Registry PowerShell Module to manage the registry with Windows PowerShell. This version supports the new improvement in .NET 4 to specify a 32-bit or 64-bit view of the registry with the Microsoft.Win32.RegistryView enumeration when you open base keys.Raptor-Plus-Plus: CS240 class project Reset IPv6: Troubleshooting Pack to reset virtual IPv6 interfaces on Windows 7 (ISATAP, Teredo, IPHTTPS and 6to4)resurection: Game for WP7SharePoint 2010 Google Maps Web Part for Sandbox and Farm Solutions: The Google Maps Web Part lets you quickly and easily add Google Maps to your Microsoft SharePoint 2010 pages. Compatible with SharePoint 2010, SharePoint 2010 SP1 and SharePoint Online, via Office 365.SPLight UTL Sharepoint 2010 BackUp / Restore UI: Sharepoint 2010 BackUp / Restore UI Sharepoint 2010 backUp restore user interface site collection backup restore graphical user interfaceVisual Image Processing: Visual Image processing for 2d or 3d real-time video or still image from camera or web cam or scanner ... XNA4LED: XNA 4.0 LED Billboard Example

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• Why Are Minimized Programs Often Slow to Open Again?

  - by Jason Fitzpatrick

  It seems particularly counterintuitive: you minimize an application because you plan on returning to it later and wish to skip shutting the application down and restarting it later, but sometimes maximizing it takes even longer than launching it fresh. What gives? Today’s Question & Answer session comes to us courtesy of SuperUser—a subdivision of Stack Exchange, a community-driven grouping of Q&A web sites. The Question SuperUser reader Bart wants to know why he’s not saving any time with application minimization: I’m working in Photoshop CS6 and multiple browsers a lot. I’m not using them all at once, so sometimes some applications are minimized to taskbar for hours or days. The problem is, when I try to maximize them from the taskbar – it sometimes takes longer than starting them! Especially Photoshop feels really weird for many seconds after finally showing up, it’s slow, unresponsive and even sometimes totally freezes for minute or two. It’s not a hardware problem as it’s been like that since always on all on my PCs. Would I also notice it after upgrading my HDD to SDD and adding RAM (my main PC holds 4 GB currently)? Could guys with powerful pcs / macs tell me – does it also happen to you? I guess OSes somehow “focus” on active software and move all the resources away from the ones that run, but are not used. Is it possible to somehow set RAM / CPU / HDD priorities or something, for let’s say, Photoshop, so it won’t slow down after long period of inactivity? So what is the deal? Why does he find himself waiting to maximize a minimized app? The Answer SuperUser contributor Allquixotic explains why: Summary The immediate problem is that the programs that you have minimized are being paged out to the “page file” on your hard disk. This symptom can be improved by installing a Solid State Disk (SSD), adding more RAM to your system, reducing the number of programs you have open, or upgrading to a newer system architecture (for instance, Ivy Bridge or Haswell). Out of these options, adding more RAM is generally the most effective solution. Explanation The default behavior of Windows is to give active applications priority over inactive applications for having a spot in RAM. When there’s significant memory pressure (meaning the system doesn’t have a lot of free RAM if it were to let every program have all the RAM it wants), it starts putting minimized programs into the page file, which means it writes out their contents from RAM to disk, and then makes that area of RAM free. That free RAM helps programs you’re actively using — say, your web browser — run faster, because if they need to claim a new segment of RAM (like when you open a new tab), they can do so. This “free” RAM is also used as page cache, which means that when active programs attempt to read data on your hard disk, that data might be cached in RAM, which prevents your hard disk from being accessed to get that data. By using the majority of your RAM for page cache, and swapping out unused programs to disk, Windows is trying to improve responsiveness of the program(s) you are actively using, by making RAM available to them, and caching the files they access in RAM instead of the hard disk. The downside of this behavior is that minimized programs can take a while to have their contents copied from the page file, on disk, back into RAM. The time increases the larger the program’s footprint in memory. This is why you experience that delay when maximizing Photoshop. RAM is many times faster than a hard disk (depending on the specific hardware, it can be up to several orders of magnitude). An SSD is considerably faster than a hard disk, but it is still slower than RAM by orders of magnitude. Having your page file on an SSD will help, but it will also wear out the SSD more quickly than usual if your page file is heavily utilized due to RAM pressure. Remedies Here is an explanation of the available remedies, and their general effectiveness: Installing more RAM: This is the recommended path. If your system does not support more RAM than you already have installed, you will need to upgrade more of your system: possibly your motherboard, CPU, chassis, power supply, etc. depending on how old it is. If it’s a laptop, chances are you’ll have to buy an entire new laptop that supports more installed RAM. When you install more RAM, you reduce memory pressure, which reduces use of the page file, which is a good thing all around. You also make available more RAM for page cache, which will make all programs that access the hard disk run faster. As of Q4 2013, my personal recommendation is that you have at least 8 GB of RAM for a desktop or laptop whose purpose is anything more complex than web browsing and email. That means photo editing, video editing/viewing, playing computer games, audio editing or recording, programming / development, etc. all should have at least 8 GB of RAM, if not more. Run fewer programs at a time: This will only work if the programs you are running do not use a lot of memory on their own. Unfortunately, Adobe Creative Suite products such as Photoshop CS6 are known for using an enormous amount of memory. This also limits your multitasking ability. It’s a temporary, free remedy, but it can be an inconvenience to close down your web browser or Word every time you start Photoshop, for instance. This also wouldn’t stop Photoshop from being swapped when minimizing it, so it really isn’t a very effective solution. It only helps in some specific situations. Install an SSD: If your page file is on an SSD, the SSD’s improved speed compared to a hard disk will result in generally improved performance when the page file has to be read from or written to. Be aware that SSDs are not designed to withstand a very frequent and constant random stream of writes; they can only be written over a limited number of times before they start to break down. Heavy use of a page file is not a particularly good workload for an SSD. You should install an SSD in combination with a large amount of RAM if you want maximum performance while preserving the longevity of the SSD. Use a newer system architecture: Depending on the age of your system, you may be using an out of date system architecture. The “system architecture” is generally defined as the “generation” (think generations like children, parents, grandparents, etc.) of the motherboard and CPU. Newer generations generally support faster I/O (input/output), better memory bandwidth, lower latency, and less contention over shared resources, instead providing dedicated links between components. For example, starting with the “Nehalem” generation (around 2009), the Front-Side Bus (FSB) was eliminated, which removed a common bottleneck, because almost all system components had to share the same FSB for transmitting data. This was replaced with a “point to point” architecture, meaning that each component gets its own dedicated “lane” to the CPU, which continues to be improved every few years with new generations. You will generally see a more significant improvement in overall system performance depending on the “gap” between your computer’s architecture and the latest one available. For example, a Pentium 4 architecture from 2004 is going to see a much more significant improvement upgrading to “Haswell” (the latest as of Q4 2013) than a “Sandy Bridge” architecture from ~2010. Links Related questions: How to reduce disk thrashing (paging)? Windows Swap (Page File): Enable or Disable? Also, just in case you’re considering it, you really shouldn’t disable the page file, as this will only make matters worse; see here. And, in case you needed extra convincing to leave the Windows Page File alone, see here and here. Have something to add to the explanation? Sound off in the the comments. Want to read more answers from other tech-savvy Stack Exchange users? Check out the full discussion thread here.     

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• Developing Schema Compare for Oracle (Part 2): Dependencies

  - by Simon Cooper

  In developing Schema Compare for Oracle, one of the issues we came across was the size of the databases. As detailed in my last blog post, we had to allow schema pre-filtering due to the number of objects in a standard Oracle database. Unfortunately, this leads to some quite tricky situations regarding object dependencies. This post explains how we deal with these dependencies. 1. Cross-schema dependencies Say, in the following database, you're populating SchemaA, and synchronizing SchemaA.Table1: SOURCE   TARGET CREATE TABLE SchemaA.Table1 ( Col1 NUMBER REFERENCES SchemaB.Table1(Col1));   CREATE TABLE SchemaA.Table1 ( Col1 VARCHAR2(100) REFERENCES SchemaB.Table1(Col1)); CREATE TABLE SchemaB.Table1 ( Col1 NUMBER PRIMARY KEY);   CREATE TABLE SchemaB.Table1 ( Col1 VARCHAR2(100) PRIMARY KEY); We need to do a rebuild of SchemaA.Table1 to change Col1 from a VARCHAR2(100) to a NUMBER. This consists of: Creating a table with the new schema Inserting data from the old table to the new table, with appropriate conversion functions (in this case, TO_NUMBER) Dropping the old table Rename new table to same name as old table Unfortunately, in this situation, the rebuild will fail at step 1, as we're trying to create a NUMBER column with a foreign key reference to a VARCHAR2(100) column. As we're only populating SchemaA, the naive implementation of the object population prefiltering (sticking a WHERE owner = 'SCHEMAA' on all the data dictionary queries) will generate an incorrect sync script. What we actually have to do is: Drop foreign key constraint on SchemaA.Table1 Rebuild SchemaB.Table1 Rebuild SchemaA.Table1, adding the foreign key constraint to the new table This means that in order to generate a correct synchronization script for SchemaA.Table1 we have to know what SchemaB.Table1 is, and that it also needs to be rebuilt to successfully rebuild SchemaA.Table1. SchemaB isn't the schema that the user wants to synchronize, but we still have to load the table and column information for SchemaB.Table1 the same way as any table in SchemaA. Fortunately, Oracle provides (mostly) complete dependency information in the dictionary views. Before we actually read the information on all the tables and columns in the database, we can get dependency information on all the objects that are either pointed at by objects in the schemas we’re populating, or point to objects in the schemas we’re populating (think about what would happen if SchemaB was being explicitly populated instead), with a suitable query on all_constraints (for foreign key relationships) and all_dependencies (for most other types of dependencies eg a function using another function). The extra objects found can then be included in the actual object population, and the sync wizard then has enough information to figure out the right thing to do when we get to actually synchronize the objects. Unfortunately, this isn’t enough. 2. Dependency chains The solution above will only get the immediate dependencies of objects in populated schemas. What if there’s a chain of dependencies? A.tbl1 -> B.tbl1 -> C.tbl1 -> D.tbl1 If we’re only populating SchemaA, the implementation above will only include B.tbl1 in the dependent objects list, whereas we might need to know about C.tbl1 and D.tbl1 as well, in order to ensure a modification on A.tbl1 can succeed. What we actually need is a graph traversal on the dependency graph that all_dependencies represents. Fortunately, we don’t have to read all the database dependency information from the server and run the graph traversal on the client computer, as Oracle provides a method of doing this in SQL – CONNECT BY. So, we can put all the dependencies we want to include together in big bag with UNION ALL, then run a SELECT ... CONNECT BY on it, starting with objects in the schema we’re populating. We should end up with all the objects that might be affected by modifications in the initial schema we’re populating. Good solution? Well, no. For one thing, it’s sloooooow. all_dependencies, on my test databases, has got over 110,000 rows in it, and the entire query, for which Oracle was creating a temporary table to hold the big bag of graph edges, was often taking upwards of two minutes. This is too long, and would only get worse for large databases. But it had some more fundamental problems than just performance. 3. Comparison dependencies Consider the following schema: SOURCE   TARGET CREATE TABLE SchemaA.Table1 ( Col1 NUMBER REFERENCES SchemaB.Table1(col1));   CREATE TABLE SchemaA.Table1 ( Col1 VARCHAR2(100)); CREATE TABLE SchemaB.Table1 ( Col1 NUMBER PRIMARY KEY);   CREATE TABLE SchemaB.Table1 ( Col1 VARCHAR2(100)); What will happen if we used the dependency algorithm above on the source & target database? Well, SchemaA.Table1 has a foreign key reference to SchemaB.Table1, so that will be included in the source database population. On the target, SchemaA.Table1 has no such reference. Therefore SchemaB.Table1 will not be included in the target database population. In the resulting comparison of the two objects models, what you will end up with is: SOURCE  TARGET SchemaA.Table1 -> SchemaA.Table1 SchemaB.Table1 -> (no object exists) When this comparison is synchronized, we will see that SchemaB.Table1 does not exist, so we will try the following sequence of actions: Create SchemaB.Table1 Rebuild SchemaA.Table1, with foreign key to SchemaB.Table1 Oops. Because the dependencies are only followed within a single database, we’ve tried to create an object that already exists. To fix this we can include any objects found as dependencies in the source or target databases in the object population of both databases. SchemaB.Table1 will then be included in the target database population, and we won’t try and create objects that already exist. All good? Well, consider the following schema (again, only explicitly populating SchemaA, and synchronizing SchemaA.Table1): SOURCE   TARGET CREATE TABLE SchemaA.Table1 ( Col1 NUMBER REFERENCES SchemaB.Table1(col1));   CREATE TABLE SchemaA.Table1 ( Col1 VARCHAR2(100)); CREATE TABLE SchemaB.Table1 ( Col1 NUMBER PRIMARY KEY);   CREATE TABLE SchemaB.Table1 ( Col1 VARCHAR2(100) PRIMARY KEY); CREATE TABLE SchemaC.Table1 ( Col1 NUMBER);   CREATE TABLE SchemaC.Table1 ( Col1 VARCHAR2(100) REFERENCES SchemaB.Table1); Although we’re now including SchemaB.Table1 on both sides of the comparison, there’s a third table (SchemaC.Table1) that we don’t know about that will cause the rebuild of SchemaB.Table1 to fail if we try and synchronize SchemaA.Table1. That’s because we’re only running the dependency query on the schemas we’re explicitly populating; to solve this issue, we would have to run the dependency query again, but this time starting the graph traversal from the objects found in the other database. Furthermore, this dependency chain could be arbitrarily extended.This leads us to the following algorithm for finding all the dependencies of a comparison: Find initial dependencies of schemas the user has selected to compare on the source and target Include these objects in both the source and target object populations Run the dependency query on the source, starting with the objects found as dependents on the target, and vice versa Repeat 2 & 3 until no more objects are found For the schema above, this will result in the following sequence of actions: Find initial dependenciesSchemaA.Table1 -> SchemaB.Table1 found on sourceNo objects found on target Include objects in both source and targetSchemaB.Table1 included in source and target Run dependency query, starting with found objectsNo objects to start with on sourceSchemaB.Table1 -> SchemaC.Table1 found on target Include objects in both source and targetSchemaC.Table1 included in source and target Run dependency query on found objectsNo objects found in sourceNo objects to start with in target Stop This will ensure that we include all the necessary objects to make any synchronization work. However, there is still the issue of query performance; the CONNECT BY on the entire database dependency graph is still too slow. After much sitting down and drawing complicated diagrams, we decided to move the graph traversal algorithm from the server onto the client (which turned out to run much faster on the client than on the server); and to ensure we don’t read the entire dependency graph onto the client we also pull the graph across in bits – we start off with dependency edges involving schemas selected for explicit population, and whenever the graph traversal comes across a dependency reference to a schema we don’t yet know about a thunk is hit that pulls in the dependency information for that schema from the database. We continue passing more dependent objects back and forth between the source and target until no more dependency references are found. This gives us the list of all the extra objects to populate in the source and target, and object population can then proceed. 4. Object blacklists and fast dependencies When we tested this solution, we were puzzled in that in some of our databases most of the system schemas (WMSYS, ORDSYS, EXFSYS, XDB, etc) were being pulled in, and this was increasing the database registration and comparison time quite significantly. After debugging, we discovered that the culprits were database tables that used one of the Oracle PL/SQL types (eg the SDO_GEOMETRY spatial type). These were creating a dependency chain from the database tables we were populating to the system schemas, and hence pulling in most of the system objects in that schema. To solve this we introduced blacklists of objects we wouldn’t follow any dependency chain through. As well as the Oracle-supplied PL/SQL types (MDSYS.SDO_GEOMETRY, ORDSYS.SI_COLOR, among others) we also decided to blacklist the entire PUBLIC and SYS schemas, as any references to those would likely lead to a blow up in the dependency graph that would massively increase the database registration time, and could result in the client running out of memory. Even with these improvements, each dependency query was taking upwards of a minute. We discovered from Oracle execution plans that there were some columns, with dependency information we required, that were querying system tables with no indexes on them! To cut a long story short, running the following query: SELECT * FROM all_tab_cols WHERE data_type_owner = ‘XDB’; results in a full table scan of the SYS.COL$ system table! This single clause was responsible for over half the execution time of the dependency query. Hence, the ‘Ignore slow dependencies’ option was born – not querying this and a couple of similar clauses to drastically speed up the dependency query execution time, at the expense of producing incorrect sync scripts in rare edge cases. Needless to say, along with the sync script action ordering, the dependency code in the database registration is one of the most complicated and most rewritten parts of the Schema Compare for Oracle engine. The beta of Schema Compare for Oracle is out now; if you find a bug in it, please do tell us so we can get it fixed!

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