Search Results

Search found 4815 results on 193 pages for 'parameterized queries'.

Page 45/193 | < Previous Page | 41 42 43 44 45 46 47 48 49 50 51 52  | Next Page >

  • SQL Profiler and Tuning Advisor for Reporting Services - what events should be selected?

    - by chris
    I've used the SQL Profiler to generate a trace file, and tuning advisor to take that trace file and provide some recommendations on db updates. However, the SQL Profiler doesn't seem to track the queries when running against a Reporting Server, the profiler doesn't seem to be capturing any of the queries. I'm logging the defaults (SQL:BatchCompleted and Starting, RPC:completed, and Sessions - Existing Connections) What events should I be capturing in SQL Profiler in order to run the tuning advisor?

    Read the article

  • SQL - when should you use "with (nolock)"

    - by Andy White
    Can someone explain the implications of using "with (nolock)" on queries, when you should/shouldn't use it? For example, if you have a banking application with high transaction rates and a lot of data in certain tables, in what types of queries would nolock be okay? Are there cases when you should always use it/never use it?

    Read the article

  • Would I want to throw an exception or an error in this PHP script?

    - by Tower
    Hi, I have a PHP script that runs database queries. Now, if a query fails, should I trigger an error or throw an exception? I noticed that if I do the latter, the script execution will stop after facing the exception. My code is as follows: if (!$this->connection[0]->query($this->query)) throw new Exception($this->connection[0]->error); What are the pros and cons of using exceptions for this kind of cases (failed queries)?

    Read the article

  • Tool for sql refactoring?

    - by C. Ross
    Is there a refactoring tool available for SQL (TSQL in particular). Is there any tool that can do automatic simplification of SQL? I have a set of views where only the top two are used, and I'd like to refactor this into only two views, hence 10+ queries into two queries.

    Read the article

  • How to span multile tables in Django

    - by ipartola
    The Django documentation gives en example like so: b = Blog.objects.get(id=1) b.entry_set.all() Which from what I understand results in 2 queries. What if I wanted to get the blog, the blog entries and all the comments associated with that entry in a number of queries that does not depend on the number of entries? Or do I have to drop down to SQL to do that?

    Read the article

  • NUmber of rows in Oracle SQL Select?

    - by twelshesgi
    I need to nkw how many records were returned in a select in oracle. Currently, I do two queries: SELECT COUNT(ITEM_ID) FROM MY_ITEMS; SELECT * FROM MY_ITEMS; I need to know the COUNT but I hate doing two queries. Is there a way to do: SELECT * FROM MY_ITEMS and then find out how many records are in there?

    Read the article

  • Are the ususal database performance-tuning tips invalide for a third-party app like Drupal

    - by Paul Strugger
    When you have a slow database app, the first suggestions that people make is to: Track the slow queries Add appropriate indexes In the case you are building your own application this is very logical, but when you use a CMS like Drupal, that are people have developed and tuned, is this approach valid? I mean, aren't Drupal tables already fine-tuned for performance? Even if I try to see which queries are the slow ones, what could I do about it? Re-write Drupal core?!?

    Read the article

  • What are the SQL Server query syntax not supported by MySQL?

    - by ANP
    I am working in a project where we are using SQL Server database currently. But recently a decision has been taken that the database will be changed to MySQL. I am not using any stored procedures, views, triggers, user defined functions, etc. But I think even then some queries written for SQL Server will not be supported by MySQL. Can anyone help: what are the things that I have to check (and change) so that all the queries will work properly for MySQL also?

    Read the article

  • How to send data many times to web browser in response to one request?

    - by robert_d
    I have a form on my web page, it allows to submit many queries to my website, every query is on a separate line in TextArea. Because waiting for all queries to complete is too long I would like to update the web page after every query completes - send result of one query to a web browser, new result should be appended to old results that are already on the web page. How to do this in ASP.NET MVC 2? I will be grateful for helpful responses.

    Read the article

  • CPU Utilization LAMP stack

    - by Max
    We've got an ec2 m2.4xlarge running Magento (centos 5.6, httpd 2.2, php 5.2.17 with eaccelerator 0.9.5.3, mysql 5.1.52). Right now we're getting a large traffic spike, and our top looks like this: top - 09:41:29 up 31 days, 1:12, 1 user, load average: 120.01, 129.03, 113.23 Tasks: 1190 total, 18 running, 1172 sleeping, 0 stopped, 0 zombie Cpu(s): 97.3%us, 1.8%sy, 0.0%ni, 0.5%id, 0.0%wa, 0.0%hi, 0.0%si, 0.4%st Mem: 71687720k total, 36898928k used, 34788792k free, 49692k buffers Swap: 880737784k total, 0k used, 880737784k free, 1586524k cached PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND 2433 mysql 15 0 23.6g 4.5g 7112 S 564.7 6.6 33607:34 mysqld 24046 apache 16 0 411m 65m 28m S 26.4 0.1 0:09.05 httpd 24360 apache 15 0 410m 60m 25m S 26.4 0.1 0:03.65 httpd 24993 apache 16 0 410m 57m 21m S 26.1 0.1 0:01.41 httpd 24838 apache 16 0 428m 74m 20m S 24.8 0.1 0:02.37 httpd 24359 apache 16 0 411m 62m 26m R 22.3 0.1 0:08.12 httpd 23850 apache 15 0 411m 64m 27m S 16.8 0.1 0:14.54 httpd 25229 apache 16 0 404m 46m 17m R 10.2 0.1 0:00.71 httpd 14594 apache 15 0 404m 63m 34m S 8.4 0.1 1:10.26 httpd 24955 apache 16 0 404m 50m 21m R 8.4 0.1 0:01.66 httpd 24313 apache 16 0 399m 46m 22m R 8.1 0.1 0:02.30 httpd 25119 apache 16 0 411m 59m 23m S 6.8 0.1 0:01.45 httpd Questions: Would giving msyqld more memory help it cache queries and react faster? If so, how? Other than splitting mysql and php to separate servers (which we're about to do) is there anything else we could/should be doing? Thanks! UPDATE: Here's our my.cnf along with the output of mysqltuner. It looks like a cache problem. Thanks again! # cat /etc/my.cnf [client] port = **** socket = /var/lib/mysql/mysql.sock [mysqld] datadir=/mnt/persistent/mysql port=**** socket=/var/lib/mysql/mysql.sock key_buffer = 512M max_allowed_packet = 64M table_cache = 1024 sort_buffer_size = 8M read_buffer_size = 4M read_rnd_buffer_size = 2M myisam_sort_buffer_size = 64M thread_cache_size = 128M tmp_table_size = 128M join_buffer_size = 1M query_cache_limit = 2M query_cache_size= 64M query_cache_type = 1 max_connections = 1000 thread_stack = 128K thread_concurrency = 48 log-bin=mysql-bin server-id = 1 wait_timeout = 300 innodb_data_home_dir = /mnt/persistent/mysql/ innodb_data_file_path = ibdata1:10M:autoextend innodb_buffer_pool_size = 20G innodb_additional_mem_pool_size = 20M innodb_log_file_size = 64M innodb_log_buffer_size = 8M innodb_flush_log_at_trx_commit = 1 innodb_lock_wait_timeout = 50 innodb_thread_concurrency = 48 ft_min_word_len=3 [myisamchk] ft_min_word_len=3 key_buffer = 128M sort_buffer_size = 128M read_buffer = 2M write_buffer = 2M # ./mysqltuner.pl >> MySQLTuner 1.2.0 - Major Hayden <[email protected]> >> Bug reports, feature requests, and downloads at http://mysqltuner.com/ >> Run with '--help' for additional options and output filtering -------- General Statistics -------------------------------------------------- [--] Skipped version check for MySQLTuner script [OK] Currently running supported MySQL version 5.1.52-log [OK] Operating on 64-bit architecture -------- Storage Engine Statistics ------------------------------------------- [--] Status: +Archive -BDB +Federated +InnoDB -ISAM -NDBCluster [--] Data in MyISAM tables: 2G (Tables: 26) [--] Data in InnoDB tables: 749M (Tables: 250) [!!] Total fragmented tables: 262 -------- Security Recommendations ------------------------------------------- -------- Performance Metrics ------------------------------------------------- [--] Up for: 31d 2h 30m 38s (680M q [253.371 qps], 2M conn, TX: 4825B, RX: 236B) [--] Reads / Writes: 89% / 11% [--] Total buffers: 20.6G global + 15.1M per thread (1000 max threads) [OK] Maximum possible memory usage: 35.4G (51% of installed RAM) [OK] Slow queries: 0% (35K/680M) [OK] Highest usage of available connections: 53% (537/1000) [OK] Key buffer size / total MyISAM indexes: 512.0M/457.2M [OK] Key buffer hit rate: 100.0% (9B cached / 264K reads) [OK] Query cache efficiency: 42.3% (260M cached / 615M selects) [!!] Query cache prunes per day: 4384652 [OK] Sorts requiring temporary tables: 0% (1K temp sorts / 38M sorts) [!!] Joins performed without indexes: 100404 [OK] Temporary tables created on disk: 17% (7M on disk / 45M total) [OK] Thread cache hit rate: 99% (537 created / 2M connections) [!!] Table cache hit rate: 0% (1K open / 946K opened) [OK] Open file limit used: 9% (453/5K) [OK] Table locks acquired immediately: 99% (758M immediate / 758M locks) [OK] InnoDB data size / buffer pool: 749.3M/20.0G -------- Recommendations ----------------------------------------------------- General recommendations: Run OPTIMIZE TABLE to defragment tables for better performance 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 Variables to adjust: query_cache_size (> 64M) join_buffer_size (> 1.0M, or always use indexes with joins) table_cache (> 1024)

    Read the article

  • mySQL Optimization Suggestions

    - by Brian Schroeter
    I'm trying to optimize our mySQL configuration for our large Magento website. The reason I believe that mySQL needs to be configured further is because New Relic has shown that our SELECT queries are taking a long time (20,000+ ms) in some categories. I ran MySQLTuner 1.3.0 and got the following results... (Disclaimer: I restarted mySQL earlier after tweaking some settings, and so the results here may not be 100% accurate): >> MySQLTuner 1.3.0 - Major Hayden <[email protected]> >> Bug reports, feature requests, and downloads at http://mysqltuner.com/ >> Run with '--help' for additional options and output filtering [OK] Currently running supported MySQL version 5.5.37-35.0 [OK] Operating on 64-bit architecture -------- Storage Engine Statistics ------------------------------------------- [--] Status: +ARCHIVE +BLACKHOLE +CSV -FEDERATED +InnoDB +MRG_MYISAM [--] Data in MyISAM tables: 7G (Tables: 332) [--] Data in InnoDB tables: 213G (Tables: 8714) [--] Data in PERFORMANCE_SCHEMA tables: 0B (Tables: 17) [--] Data in MEMORY tables: 0B (Tables: 353) [!!] Total fragmented tables: 5492 -------- Security Recommendations ------------------------------------------- [!!] User '@host5.server1.autopartsnetwork.com' has no password set. [!!] User '@localhost' has no password set. [!!] User 'root@%' has no password set. -------- Performance Metrics ------------------------------------------------- [--] Up for: 5h 3m 4s (5M q [317.443 qps], 42K conn, TX: 18B, RX: 2B) [--] Reads / Writes: 95% / 5% [--] Total buffers: 35.5G global + 184.5M per thread (1024 max threads) [!!] Maximum possible memory usage: 220.0G (174% of installed RAM) [OK] Slow queries: 0% (6K/5M) [OK] Highest usage of available connections: 5% (61/1024) [OK] Key buffer size / total MyISAM indexes: 512.0M/3.1G [OK] Key buffer hit rate: 100.0% (102M cached / 45K reads) [OK] Query cache efficiency: 66.9% (3M cached / 5M selects) [!!] Query cache prunes per day: 3486361 [OK] Sorts requiring temporary tables: 0% (0 temp sorts / 812K sorts) [!!] Joins performed without indexes: 1328 [OK] Temporary tables created on disk: 11% (126K on disk / 1M total) [OK] Thread cache hit rate: 99% (61 created / 42K connections) [!!] Table cache hit rate: 19% (9K open / 49K opened) [OK] Open file limit used: 2% (712/25K) [OK] Table locks acquired immediately: 100% (5M immediate / 5M locks) [!!] InnoDB buffer pool / data size: 32.0G/213.4G [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 Reduce your overall MySQL memory footprint for system stability Enable the slow query log to troubleshoot bad queries Increasing the query_cache size over 128M may reduce performance 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: *** MySQL's maximum memory usage is dangerously high *** *** Add RAM before increasing MySQL buffer variables *** query_cache_size (> 512M) [see warning above] join_buffer_size (> 128.0M, or always use indexes with joins) table_cache (> 12288) innodb_buffer_pool_size (>= 213G) My my.cnf configuration is as follows... [client] port = 3306 [mysqld_safe] nice = 0 [mysqld] tmpdir = /var/lib/mysql/tmp user = mysql port = 3306 skip-external-locking character-set-server = utf8 collation-server = utf8_general_ci event_scheduler = 0 key_buffer = 512M max_allowed_packet = 64M thread_stack = 512K thread_cache_size = 512 sort_buffer_size = 24M read_buffer_size = 8M read_rnd_buffer_size = 24M join_buffer_size = 128M # for some nightly processes client sessions set the join buffer to 8 GB auto-increment-increment = 1 auto-increment-offset = 1 myisam-recover = BACKUP max_connections = 1024 # max connect errors artificially high to support behaviors of NetScaler monitors max_connect_errors = 999999 concurrent_insert = 2 connect_timeout = 5 wait_timeout = 180 net_read_timeout = 120 net_write_timeout = 120 back_log = 128 # this table_open_cache might be too low because of MySQL bugs #16244691 and #65384) table_open_cache = 12288 tmp_table_size = 512M max_heap_table_size = 512M bulk_insert_buffer_size = 512M open-files-limit = 8192 open-files = 1024 query_cache_type = 1 # large query limit supports SOAP and REST API integrations query_cache_limit = 4M # larger than 512 MB query cache size is problematic; this is typically ~60% full query_cache_size = 512M # set to true on read slaves read_only = false slow_query_log_file = /var/log/mysql/slow.log slow_query_log = 0 long_query_time = 0.2 expire_logs_days = 10 max_binlog_size = 1024M binlog_cache_size = 32K sync_binlog = 0 # SSD RAID10 technically has a write capacity of 10000 IOPS innodb_io_capacity = 400 innodb_file_per_table innodb_table_locks = true innodb_lock_wait_timeout = 30 # These servers have 80 CPU threads; match 1:1 innodb_thread_concurrency = 48 innodb_commit_concurrency = 2 innodb_support_xa = true innodb_buffer_pool_size = 32G innodb_file_per_table innodb_flush_log_at_trx_commit = 1 innodb_log_buffer_size = 2G skip-federated [mysqldump] quick quote-names single-transaction max_allowed_packet = 64M I have a monster of a server here to power our site because our catalog is very large (300,000 simple SKUs), and I'm just wondering if I'm missing anything that I can configure further. :-) Thanks!

    Read the article

  • BIND no longer responds to AXFR Requests

    - by djsumdog
    Recently we moved our primary external DNS server. It has three caching DNS slaves in front of it provided by our ISP. They've told us they've started getting access denied requests when doing zone transfers (AXFR). If I add in my own IPs to the allow-transfer list, I also get a transfer failed when using dig with the AXFR argument. Here is what my bind configuration looks like: options { directory "/var/lib/named"; dump-file "/var/log/named_dump.db"; zone-statistics yes; statistics-file "/var/log/named.stats"; listen-on-v6 { any; }; notify-source 10.19.0.68 port 53; querylog yes; notify yes; allow-transfer { 127.0.0.1; //localhost 1.1.1.1; //public dns slave 1 2.2.2.2; //public dns slave 2 3.3.3.3; //public dns slave 3 }; also-notify { 1.1.1.1; //public dns slave 1 2.2.2.2; //public dns slave 2 3.3.3.3; //public dns slave 3 }; include "/etc/named.d/forwarders.conf"; }; logging { channel simple_log { file "/var/log/bind.log" versions 10 size 3m; severity info; print-time yes; print-severity yes; print-category yes; }; category default{ simple_log; }; channel log_zone_transfers { file "/var/log/axfr.log" versions 10 size 3m; print-time yes; print-category yes; print-severity yes; }; category xfer-out { log_zone_transfers; }; channel log_notify { file "/var/log/notify.log" versions 10 size 3m; print-time yes; print-category yes; print-severity yes; }; category notify { log_notify; }; channel queries { file "/var/log/queries.log" versions 10 size 30m; print-time yes; severity info; print-category yes; print-severity yes; }; category queries { queries; }; }; zone "." in { type hint; file "root.hint"; }; zone "localhost" in { type master; file "localhost.zone"; }; zone "0.0.127.in-addr.arpa" in { type master; file "127.0.0.zone"; }; include "/etc/named.conf.include"; zone "example.net " { type master; file "/var/lib/named/master/example.net.hosts"; }; zone "example.com " { type master; file "/var/lib/named/master/example.com.hosts"; }; ## -- other master files -- And the errors in the xfer log look like the following: 29-Oct-2012 14:20:02.806 xfer-out: info: client 1.1.1.1#59069: bad zone transfer request: 'example.com./IN': non-authoritative zone (NOTAUTH) I've tried adding allow-transfer parameters directly on the zone files and still get failed transfers. Any idea what I'm doing wrong?

    Read the article

  • Intermittent wired network issues in 14.04

    - by Tommy Brunn
    Since yesterday, my wired network connection has been dropping for a couple of seconds every 30 seconds or so. To my knowledge, I had not made any changes to my network. Output of ifconfig -a: ? ~ ifconfig -a eth0 Link encap:Ethernet HWaddr 6c:f0:49:b9:b1:7f inet addr:192.168.0.16 Bcast:192.168.0.255 Mask:255.255.255.0 inet6 addr: fe80::6ef0:49ff:feb9:b17f/64 Scope:Link UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1 RX packets:11597 errors:0 dropped:0 overruns:0 frame:0 TX packets:9783 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:1000 RX bytes:10101682 (10.1 MB) TX bytes:1215142 (1.2 MB) Interrupt:48 Base address:0x8000 lo Link encap:Local Loopback inet addr:127.0.0.1 Mask:255.0.0.0 inet6 addr: ::1/128 Scope:Host UP LOOPBACK RUNNING MTU:65536 Metric:1 RX packets:96691 errors:0 dropped:0 overruns:0 frame:0 TX packets:96691 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:0 RX bytes:13594355 (13.5 MB) TX bytes:13594355 (13.5 MB) lspci |grep Ethernet: 04:00.0 Ethernet controller: Realtek Semiconductor Co., Ltd. RTL8111/8168/8411 PCI Express Gigabit Ethernet Controller (rev 03) Pinging my router: ? ~ ping 192.168.0.1 PING 192.168.0.1 (192.168.0.1) 56(84) bytes of data. 64 bytes from 192.168.0.1: icmp_seq=1 ttl=64 time=0.435 ms 64 bytes from 192.168.0.1: icmp_seq=2 ttl=64 time=0.571 ms ping: sendmsg: Network is unreachable ping: sendmsg: Network is unreachable ping: sendmsg: Network is unreachable ping: sendmsg: Network is unreachable ping: sendmsg: Network is unreachable 64 bytes from 192.168.0.1: icmp_seq=8 ttl=64 time=1.03 ms And the output of route: ? ~ route Kernel IP routing table Destination Gateway Genmask Flags Metric Ref Use Iface default 192.168.0.1 0.0.0.0 UG 0 0 0 eth0 192.168.0.0 * 255.255.255.0 U 1 0 0 eth0 Some messages from /var/logs/syslog: ? ~ tail -f /var/log/syslog Jun 6 10:37:34 lolbox dhclient: RCV: Advertise message on eth0 from fe80::120d:7fff:fe97:9d54. Jun 6 10:37:34 lolbox dhclient: IA_NA status code NoAddrsAvail. Jun 6 10:37:37 lolbox dnsmasq[1138]: Maximum number of concurrent DNS queries reached (max: 150) Jun 6 10:37:37 lolbox dnsmasq[1362]: Maximum number of concurrent DNS queries reached (max: 150) Jun 6 10:37:39 lolbox dhclient: XMT: Solicit on eth0, interval 8660ms. Jun 6 10:37:39 lolbox dhclient: RCV: Advertise message on eth0 from fe80::120d:7fff:fe97:9d54. Jun 6 10:37:39 lolbox dhclient: IA_NA status code NoAddrsAvail. Jun 6 10:37:47 lolbox dhclient: XMT: Solicit on eth0, interval 16820ms. Jun 6 10:37:47 lolbox dhclient: RCV: Advertise message on eth0 from fe80::120d:7fff:fe97:9d54. Jun 6 10:37:47 lolbox dhclient: IA_NA status code NoAddrsAvail. Jun 6 10:38:04 lolbox dhclient: XMT: Solicit on eth0, interval 34410ms. Jun 6 10:38:04 lolbox dhclient: RCV: Advertise message on eth0 from fe80::120d:7fff:fe97:9d54. Jun 6 10:38:04 lolbox dhclient: IA_NA status code NoAddrsAvail. Jun 6 10:38:16 lolbox NetworkManager[862]: <warn> (eth0): DHCPv6 request timed out. Jun 6 10:38:16 lolbox NetworkManager[862]: <info> (eth0): canceled DHCP transaction, DHCP client pid 13045 Jun 6 10:38:16 lolbox NetworkManager[862]: <info> Activation (eth0) Stage 4 of 5 (IPv6 Configure Timeout) scheduled... Jun 6 10:38:16 lolbox NetworkManager[862]: <info> Activation (eth0) Stage 4 of 5 (IPv6 Configure Timeout) started... Jun 6 10:38:16 lolbox NetworkManager[862]: <info> (eth0): device state change: activated -> failed (reason 'ip-config-unavailable') [100 120 5] Jun 6 10:38:16 lolbox NetworkManager[862]: <info> NetworkManager state is now DISCONNECTED Jun 6 10:38:16 lolbox NetworkManager[862]: <warn> Activation (eth0) failed for connection 'Wired connection 1' Jun 6 10:38:16 lolbox NetworkManager[862]: <info> Activation (eth0) Stage 4 of 5 (IPv6 Configure Timeout) complete. Jun 6 10:38:16 lolbox NetworkManager[862]: <info> (eth0): device state change: failed -> disconnected (reason 'none') [120 30 0] Jun 6 10:38:16 lolbox NetworkManager[862]: <info> (eth0): deactivating device (reason 'none') [0] Jun 6 10:37:34 lolbox whoopsie[1133]: online Jun 6 10:38:16 lolbox whoopsie[1133]: offline Jun 6 10:38:16 lolbox dbus[485]: [system] Activating service name='org.freedesktop.nm_dispatcher' (using servicehelper) Jun 6 10:38:16 lolbox dbus[485]: [system] Successfully activated service 'org.freedesktop.nm_dispatcher' Jun 6 10:38:16 lolbox NetworkManager[862]: <info> (eth0): canceled DHCP transaction, DHCP client pid 13044 Jun 6 10:38:16 lolbox NetworkManager[862]: <warn> DNS: plugin dnsmasq update failed Jun 6 10:38:16 lolbox NetworkManager[862]: <info> Removing DNS information from /sbin/resolvconf Jun 6 10:38:16 lolbox avahi-daemon[619]: Withdrawing address record for fe80::6ef0:49ff:feb9:b17f on eth0. Jun 6 10:38:16 lolbox avahi-daemon[619]: Leaving mDNS multicast group on interface eth0.IPv6 with address fe80::6ef0:49ff:feb9:b17f. Jun 6 10:38:16 lolbox avahi-daemon[619]: Interface eth0.IPv6 no longer relevant for mDNS. Jun 6 10:38:16 lolbox avahi-daemon[619]: Withdrawing address record for 192.168.0.16 on eth0. Jun 6 10:38:16 lolbox avahi-daemon[619]: Leaving mDNS multicast group on interface eth0.IPv4 with address 192.168.0.16. Jun 6 10:38:16 lolbox avahi-daemon[619]: Interface eth0.IPv4 no longer relevant for mDNS. Jun 6 10:38:16 lolbox dnsmasq[1362]: setting upstream servers from DBus Jun 6 10:38:17 lolbox avahi-daemon[619]: Joining mDNS multicast group on interface eth0.IPv6 with address fe80::6ef0:49ff:feb9:b17f. Jun 6 10:38:17 lolbox avahi-daemon[619]: New relevant interface eth0.IPv6 for mDNS. Jun 6 10:38:17 lolbox avahi-daemon[619]: Registering new address record for fe80::6ef0:49ff:feb9:b17f on eth0.*. Jun 6 10:38:18 lolbox dnsmasq[1138]: no servers found in /var/run/dnsmasq/resolv.conf, will retry Jun 6 10:38:18 lolbox NetworkManager[862]: <info> Auto-activating connection 'Wired connection 1'. Jun 6 10:38:18 lolbox NetworkManager[862]: <info> Activation (eth0) starting connection 'Wired connection 1' Jun 6 10:38:18 lolbox NetworkManager[862]: <info> (eth0): device state change: disconnected -> prepare (reason 'none') [30 40 0] Jun 6 10:38:18 lolbox NetworkManager[862]: <info> NetworkManager state is now CONNECTING Jun 6 10:38:18 lolbox NetworkManager[862]: <info> Activation (eth0) Stage 1 of 5 (Device Prepare) scheduled... Jun 6 10:38:18 lolbox NetworkManager[862]: <info> Activation (eth0) Stage 1 of 5 (Device Prepare) started... Jun 6 10:38:18 lolbox NetworkManager[862]: <info> Activation (eth0) Stage 2 of 5 (Device Configure) scheduled... Jun 6 10:38:18 lolbox NetworkManager[862]: <info> Activation (eth0) Stage 1 of 5 (Device Prepare) complete. Jun 6 10:38:18 lolbox NetworkManager[862]: <info> Activation (eth0) Stage 2 of 5 (Device Configure) starting... Jun 6 10:38:18 lolbox NetworkManager[862]: <info> (eth0): device state change: prepare -> config (reason 'none') [40 50 0] Jun 6 10:38:18 lolbox NetworkManager[862]: <info> Activation (eth0) Stage 2 of 5 (Device Configure) successful. Jun 6 10:38:18 lolbox NetworkManager[862]: <info> Activation (eth0) Stage 3 of 5 (IP Configure Start) scheduled. Jun 6 10:38:18 lolbox NetworkManager[862]: <info> Activation (eth0) Stage 2 of 5 (Device Configure) complete. Jun 6 10:38:18 lolbox NetworkManager[862]: <info> Activation (eth0) Stage 3 of 5 (IP Configure Start) started... Jun 6 10:38:18 lolbox NetworkManager[862]: <info> (eth0): device state change: config -> ip-config (reason 'none') [50 70 0] Jun 6 10:38:18 lolbox NetworkManager[862]: <info> Activation (eth0) Beginning DHCPv4 transaction (timeout in 45 seconds) Jun 6 10:38:18 lolbox NetworkManager[862]: <info> dhclient started with pid 13160 Jun 6 10:38:18 lolbox NetworkManager[862]: <info> Activation (eth0) Beginning DHCPv6 transaction (timeout in 45 seconds) Jun 6 10:38:18 lolbox NetworkManager[862]: <info> dhclient started with pid 13161 Jun 6 10:38:18 lolbox NetworkManager[862]: <info> Activation (eth0) Stage 3 of 5 (IP Configure Start) complete. Jun 6 10:38:18 lolbox avahi-daemon[619]: Withdrawing address record for fe80::6ef0:49ff:feb9:b17f on eth0. Jun 6 10:38:18 lolbox avahi-daemon[619]: Leaving mDNS multicast group on interface eth0.IPv6 with address fe80::6ef0:49ff:feb9:b17f. Jun 6 10:38:18 lolbox avahi-daemon[619]: Interface eth0.IPv6 no longer relevant for mDNS. Jun 6 10:38:18 lolbox dhclient: Internet Systems Consortium DHCP Client 4.2.4 Jun 6 10:38:18 lolbox dhclient: Copyright 2004-2012 Internet Systems Consortium. Jun 6 10:38:18 lolbox dhclient: All rights reserved. Jun 6 10:38:18 lolbox dhclient: For info, please visit https://www.isc.org/software/dhcp/ Jun 6 10:38:18 lolbox dhclient: Jun 6 10:38:19 lolbox dhclient: Internet Systems Consortium DHCP Client 4.2.4 Jun 6 10:38:19 lolbox dhclient: Copyright 2004-2012 Internet Systems Consortium. Jun 6 10:38:19 lolbox dhclient: All rights reserved. Jun 6 10:38:19 lolbox dhclient: For info, please visit https://www.isc.org/software/dhcp/ Jun 6 10:38:19 lolbox dhclient: Jun 6 10:38:19 lolbox NetworkManager[862]: <info> (eth0): DHCPv4 state changed nbi -> preinit Jun 6 10:38:19 lolbox dhclient: Bound to *:546 Jun 6 10:38:19 lolbox dhclient: Listening on Socket/eth0 Jun 6 10:38:19 lolbox dhclient: Sending on Socket/eth0 Jun 6 10:38:19 lolbox NetworkManager[862]: <info> (eth0): DHCPv6 state changed nbi -> preinit6 Jun 6 10:38:19 lolbox dhclient: Listening on LPF/eth0/6c:f0:49:b9:b1:7f Jun 6 10:38:19 lolbox dhclient: Sending on LPF/eth0/6c:f0:49:b9:b1:7f Jun 6 10:38:19 lolbox dhclient: Sending on Socket/fallback Jun 6 10:38:19 lolbox dhclient: DHCPREQUEST of 192.168.0.16 on eth0 to 255.255.255.255 port 67 (xid=0x3fc9376d) Jun 6 10:38:19 lolbox dhclient: XMT: Solicit on eth0, interval 1020ms. Jun 6 10:38:19 lolbox dhclient: send_packet6: Cannot assign requested address Jun 6 10:38:19 lolbox dhclient: dhc6: send_packet6() sent -1 of 77 bytes Jun 6 10:38:20 lolbox dhclient: DHCPACK of 192.168.0.16 from 192.168.0.1 Jun 6 10:38:20 lolbox dhclient: bound to 192.168.0.16 -- renewal in 41481 seconds. Jun 6 10:38:20 lolbox NetworkManager[862]: <info> (eth0): DHCPv4 state changed preinit -> reboot Jun 6 10:38:20 lolbox NetworkManager[862]: <info> address 192.168.0.16 Jun 6 10:38:20 lolbox NetworkManager[862]: <info> prefix 24 (255.255.255.0) Jun 6 10:38:20 lolbox NetworkManager[862]: <info> gateway 192.168.0.1 Jun 6 10:38:20 lolbox NetworkManager[862]: <info> nameserver '83.255.245.11' Jun 6 10:38:20 lolbox NetworkManager[862]: <info> nameserver '193.150.193.150' Jun 6 10:38:20 lolbox NetworkManager[862]: <info> Activation (eth0) Stage 5 of 5 (IPv4 Configure Commit) scheduled... Jun 6 10:38:20 lolbox NetworkManager[862]: <info> Activation (eth0) Stage 5 of 5 (IPv4 Commit) started... Jun 6 10:38:20 lolbox avahi-daemon[619]: Joining mDNS multicast group on interface eth0.IPv4 with address 192.168.0.16. Jun 6 10:38:20 lolbox avahi-daemon[619]: New relevant interface eth0.IPv4 for mDNS. Jun 6 10:38:20 lolbox avahi-daemon[619]: Registering new address record for 192.168.0.16 on eth0.IPv4. Jun 6 10:38:20 lolbox dhclient: XMT: Solicit on eth0, interval 2110ms. Jun 6 10:38:20 lolbox dhclient: send_packet6: Cannot assign requested address Jun 6 10:38:20 lolbox dhclient: dhc6: send_packet6() sent -1 of 77 bytes Jun 6 10:38:20 lolbox avahi-daemon[619]: Joining mDNS multicast group on interface eth0.IPv6 with address fe80::6ef0:49ff:feb9:b17f. Jun 6 10:38:20 lolbox avahi-daemon[619]: New relevant interface eth0.IPv6 for mDNS. Jun 6 10:38:20 lolbox avahi-daemon[619]: Registering new address record for fe80::6ef0:49ff:feb9:b17f on eth0.*. Jun 6 10:38:21 lolbox NetworkManager[862]: <info> (eth0): device state change: ip-config -> secondaries (reason 'none') [70 90 0] Jun 6 10:38:21 lolbox NetworkManager[862]: <info> Activation (eth0) Stage 5 of 5 (IPv4 Commit) complete. Jun 6 10:38:21 lolbox NetworkManager[862]: <info> (eth0): device state change: secondaries -> activated (reason 'none') [90 100 0] Jun 6 10:38:21 lolbox NetworkManager[862]: <info> NetworkManager state is now CONNECTED_GLOBAL Jun 6 10:38:21 lolbox NetworkManager[862]: <info> Policy set 'Wired connection 1' (eth0) as default for IPv4 routing and DNS. Jun 6 10:38:21 lolbox NetworkManager[862]: <info> Writing DNS information to /sbin/resolvconf Jun 6 10:38:21 lolbox dnsmasq[1362]: setting upstream servers from DBus Jun 6 10:38:21 lolbox dnsmasq[1362]: using nameserver 127.0.0.1#53 Jun 6 10:38:21 lolbox dnsmasq[1362]: using nameserver 193.150.193.150#53 Jun 6 10:38:21 lolbox dnsmasq[1362]: using nameserver 83.255.245.11#53 Jun 6 10:38:21 lolbox NetworkManager[862]: <info> Activation (eth0) successful, device activated. Jun 6 10:38:21 lolbox whoopsie[1133]: message repeated 2 times: [ offline] Jun 6 10:38:21 lolbox whoopsie[1133]: online Jun 6 10:38:21 lolbox ntpdate[13217]: Can't find host ntp.ubuntu.com: Name or service not known (-2) Jun 6 10:38:21 lolbox ntpdate[13217]: no servers can be used, exiting Jun 6 10:38:22 lolbox dnsmasq[1138]: reading /var/run/dnsmasq/resolv.conf Jun 6 10:38:22 lolbox dnsmasq[1138]: using nameserver 127.0.1.1#53 Jun 6 10:38:22 lolbox dhclient: XMT: Solicit on eth0, interval 4080ms. Jun 6 10:38:22 lolbox dhclient: RCV: Advertise message on eth0 from fe80::120d:7fff:fe97:9d54. Jun 6 10:38:22 lolbox dhclient: IA_NA status code NoAddrsAvail. Jun 6 10:38:26 lolbox dhclient: XMT: Solicit on eth0, interval 8450ms. Jun 6 10:38:26 lolbox dhclient: RCV: Advertise message on eth0 from fe80::120d:7fff:fe97:9d54. Jun 6 10:38:26 lolbox dhclient: IA_NA status code NoAddrsAvail. Jun 6 10:38:35 lolbox dhclient: XMT: Solicit on eth0, interval 16630ms. Jun 6 10:38:35 lolbox dhclient: RCV: Advertise message on eth0 from fe80::120d:7fff:fe97:9d54. Jun 6 10:38:35 lolbox dhclient: IA_NA status code NoAddrsAvail. Jun 6 10:38:51 lolbox dhclient: XMT: Solicit on eth0, interval 34860ms. Jun 6 10:38:51 lolbox dhclient: RCV: Advertise message on eth0 from fe80::120d:7fff:fe97:9d54. Jun 6 10:38:51 lolbox dhclient: IA_NA status code NoAddrsAvail. Jun 6 10:38:58 lolbox dnsmasq[1138]: Maximum number of concurrent DNS queries reached (max: 150) Jun 6 10:38:58 lolbox dnsmasq[1362]: Maximum number of concurrent DNS queries reached (max: 150) Jun 6 10:39:04 lolbox NetworkManager[862]: <warn> (eth0): DHCPv6 request timed out. Jun 6 10:39:04 lolbox NetworkManager[862]: <info> (eth0): canceled DHCP transaction, DHCP client pid 13161 Jun 6 10:39:04 lolbox NetworkManager[862]: <info> Activation (eth0) Stage 4 of 5 (IPv6 Configure Timeout) scheduled... Jun 6 10:39:04 lolbox NetworkManager[862]: <info> Activation (eth0) Stage 4 of 5 (IPv6 Configure Timeout) started... Jun 6 10:39:04 lolbox NetworkManager[862]: <info> (eth0): device state change: activated -> failed (reason 'ip-config-unavailable') [100 120 5] Jun 6 10:39:04 lolbox NetworkManager[862]: <info> NetworkManager state is now DISCONNECTED Jun 6 10:39:04 lolbox NetworkManager[862]: <warn> Activation (eth0) failed for connection 'Wired connection 1' Jun 6 10:38:22 lolbox whoopsie[1133]: online Jun 6 10:39:04 lolbox whoopsie[1133]: offline Jun 6 10:39:04 lolbox NetworkManager[862]: <info> Activation (eth0) Stage 4 of 5 (IPv6 Configure Timeout) complete. Jun 6 10:39:04 lolbox dbus[485]: [system] Activating service name='org.freedesktop.nm_dispatcher' (using servicehelper) Jun 6 10:39:04 lolbox NetworkManager[862]: <info> (eth0): device state change: failed -> disconnected (reason 'none') [120 30 0] Jun 6 10:39:04 lolbox NetworkManager[862]: <info> (eth0): deactivating device (reason 'none') [0] Jun 6 10:39:04 lolbox dbus[485]: [system] Successfully activated service 'org.freedesktop.nm_dispatcher' Jun 6 10:39:04 lolbox NetworkManager[862]: <info> (eth0): canceled DHCP transaction, DHCP client pid 13160 Jun 6 10:39:04 lolbox avahi-daemon[619]: Withdrawing address record for fe80::6ef0:49ff:feb9:b17f on eth0. Jun 6 10:39:04 lolbox avahi-daemon[619]: Leaving mDNS multicast group on interface eth0.IPv6 with address fe80::6ef0:49ff:feb9:b17f. Jun 6 10:39:04 lolbox avahi-daemon[619]: Interface eth0.IPv6 no longer relevant for mDNS. Jun 6 10:39:04 lolbox avahi-daemon[619]: Withdrawing address record for 192.168.0.16 on eth0. Jun 6 10:39:04 lolbox avahi-daemon[619]: Leaving mDNS multicast group on interface eth0.IPv4 with address 192.168.0.16. Jun 6 10:39:04 lolbox avahi-daemon[619]: Interface eth0.IPv4 no longer relevant for mDNS. Jun 6 10:39:04 lolbox NetworkManager[862]: <warn> DNS: plugin dnsmasq update failed Jun 6 10:39:04 lolbox NetworkManager[862]: <info> Removing DNS information from /sbin/resolvconf Jun 6 10:39:04 lolbox dnsmasq[1362]: setting upstream servers from DBus Jun 6 10:39:05 lolbox avahi-daemon[619]: Joining mDNS multicast group on interface eth0.IPv6 with address fe80::6ef0:49ff:feb9:b17f. Jun 6 10:39:05 lolbox avahi-daemon[619]: New relevant interface eth0.IPv6 for mDNS. Jun 6 10:39:05 lolbox avahi-daemon[619]: Registering new address record for fe80::6ef0:49ff:feb9:b17f on eth0.*. Jun 6 10:39:06 lolbox dnsmasq[1138]: no servers found in /var/run/dnsmasq/resolv.conf, will retry Jun 6 10:39:07 lolbox NetworkManager[862]: <info> Auto-activating connection 'Wired connection 1'. Jun 6 10:39:07 lolbox NetworkManager[862]: <info> Activation (eth0) starting connection 'Wired connection 1' Jun 6 10:39:07 lolbox NetworkManager[862]: <info> (eth0): device state change: disconnected -> prepare (reason 'none') [30 40 0] Jun 6 10:39:07 lolbox NetworkManager[862]: <info> NetworkManager state is now CONNECTING Jun 6 10:39:07 lolbox NetworkManager[862]: <info> Activation (eth0) Stage 1 of 5 (Device Prepare) scheduled... Jun 6 10:39:07 lolbox NetworkManager[862]: <info> Activation (eth0) Stage 1 of 5 (Device Prepare) started... Jun 6 10:39:07 lolbox NetworkManager[862]: <info> Activation (eth0) Stage 2 of 5 (Device Configure) scheduled... Jun 6 10:39:07 lolbox NetworkManager[862]: <info> Activation (eth0) Stage 1 of 5 (Device Prepare) complete. Jun 6 10:39:07 lolbox NetworkManager[862]: <info> Activation (eth0) Stage 2 of 5 (Device Configure) starting... Jun 6 10:39:07 lolbox NetworkManager[862]: <info> (eth0): device state change: prepare -> config (reason 'none') [40 50 0] Jun 6 10:39:07 lolbox NetworkManager[862]: <info> Activation (eth0) Stage 2 of 5 (Device Configure) successful. Jun 6 10:39:07 lolbox NetworkManager[862]: <info> Activation (eth0) Stage 3 of 5 (IP Configure Start) scheduled. Jun 6 10:39:07 lolbox NetworkManager[862]: <info> Activation (eth0) Stage 2 of 5 (Device Configure) complete. Jun 6 10:39:07 lolbox NetworkManager[862]: <info> Activation (eth0) Stage 3 of 5 (IP Configure Start) started... Jun 6 10:39:07 lolbox NetworkManager[862]: <info> (eth0): device state change: config -> ip-config (reason 'none') [50 70 0] Jun 6 10:39:07 lolbox NetworkManager[862]: <info> Activation (eth0) Beginning DHCPv4 transaction (timeout in 45 seconds) Jun 6 10:39:07 lolbox NetworkManager[862]: <info> dhclient started with pid 13270 Jun 6 10:39:07 lolbox NetworkManager[862]: <info> Activation (eth0) Beginning DHCPv6 transaction (timeout in 45 seconds) Jun 6 10:39:07 lolbox NetworkManager[862]: <info> dhclient started with pid 13271 Jun 6 10:39:07 lolbox NetworkManager[862]: <info> Activation (eth0) Stage 3 of 5 (IP Configure Start) complete. Jun 6 10:39:07 lolbox avahi-daemon[619]: Withdrawing address record for fe80::6ef0:49ff:feb9:b17f on eth0. Jun 6 10:39:07 lolbox avahi-daemon[619]: Leaving mDNS multicast group on interface eth0.IPv6 with address fe80::6ef0:49ff:feb9:b17f. Jun 6 10:39:07 lolbox avahi-daemon[619]: Interface eth0.IPv6 no longer relevant for mDNS. Jun 6 10:39:07 lolbox dhclient: Internet Systems Consortium DHCP Client 4.2.4 Jun 6 10:39:07 lolbox dhclient: Copyright 2004-2012 Internet Systems Consortium. Jun 6 10:39:07 lolbox dhclient: All rights reserved. Jun 6 10:39:07 lolbox dhclient: For info, please visit https://www.isc.org/software/dhcp/ Jun 6 10:39:07 lolbox dhclient: Jun 6 10:39:08 lolbox dhclient: Internet Systems Consortium DHCP Client 4.2.4 Jun 6 10:39:08 lolbox dhclient: Copyright 2004-2012 Internet Systems Consortium. Jun 6 10:39:08 lolbox dhclient: All rights reserved. Jun 6 10:39:08 lolbox dhclient: For info, please visit https://www.isc.org/software/dhcp/ Jun 6 10:39:08 lolbox dhclient: Jun 6 10:39:08 lolbox dhclient: Bound to *:546 Jun 6 10:39:08 lolbox dhclient: Listening on Socket/eth0 Jun 6 10:39:08 lolbox dhclient: Sending on Socket/eth0 Jun 6 10:39:08 lolbox kernel: [ 1446.098590] type=1400 audit(1402043948.002:75): apparmor="DENIED" operation="signal" profile="/usr/lib/NetworkManager/nm-dhcp-client.action" pid=13273 comm="nm-dhcp-client." requested_mask="send" denied_mask="send" signal=term peer="/sbin/dhclient" Jun 6 10:39:08 lolbox kernel: [ 1446.098599] type=1400 audit(1402043948.002:76): apparmor="DENIED" operation="signal" profile="/sbin/dhclient" pid=13273 comm="nm-dhcp-client." requested_mask="receive" denied_mask="receive" signal=term peer="/usr/lib/NetworkManager/nm-dhcp-client.action" Jun 6 10:39:08 lolbox NetworkManager[862]: <info> (eth0): DHCPv4 state changed nbi -> preinit Jun 6 10:39:08 lolbox dhclient: Listening on LPF/eth0/6c:f0:49:b9:b1:7f Jun 6 10:39:08 lolbox dhclient: Sending on LPF/eth0/6c:f0:49:b9:b1:7f Jun 6 10:39:08 lolbox dhclient: Sending on Socket/fallback Jun 6 10:39:08 lolbox dhclient: DHCPREQUEST of 192.168.0.16 on eth0 to 255.255.255.255 port 67 (xid=0x3e0183b9) Jun 6 10:39:08 lolbox dhclient: XMT: Solicit on eth0, interval 1050ms. Jun 6 10:39:08 lolbox dhclient: send_packet6: Cannot assign requested address Jun 6 10:39:08 lolbox dhclient: dhc6: send_packet6() sent -1 of 77 bytes Jun 6 10:39:09 lolbox dhclient: DHCPACK of 192.168.0.16 from 192.168.0.1 Jun 6 10:39:09 lolbox dhclient: bound to 192.168.0.16 -- renewal in 35498 seconds. Jun 6 10:39:09 lolbox NetworkManager[862]: <info> (eth0): DHCPv4 state changed preinit -> reboot Jun 6 10:39:09 lolbox NetworkManager[862]: <info> address 192.168.0.16 Jun 6 10:39:09 lolbox NetworkManager[862]: <info> prefix 24 (255.255.255.0) Jun 6 10:39:09 lolbox NetworkManager[862]: <info> gateway 192.168.0.1 Jun 6 10:39:09 lolbox NetworkManager[862]: <info> nameserver '83.255.245.11' Jun 6 10:39:09 lolbox NetworkManager[862]: <info> nameserver '193.150.193.150' Jun 6 10:39:09 lolbox NetworkManager[862]: <info> Activation (eth0) Stage 5 of 5 (IPv4 Configure Commit) scheduled... Jun 6 10:39:09 lolbox NetworkManager[862]: <info> Activation (eth0) Stage 5 of 5 (IPv4 Commit) started... Jun 6 10:39:09 lolbox avahi-daemon[619]: Joining mDNS multicast group on interface eth0.IPv4 with address 192.168.0.16. Jun 6 10:39:09 lolbox avahi-daemon[619]: New relevant interface eth0.IPv4 for mDNS. Jun 6 10:39:09 lolbox avahi-daemon[619]: Registering new address record for 192.168.0.16 on eth0.IPv4. Jun 6 10:39:09 lolbox avahi-daemon[619]: Joining mDNS multicast group on interface eth0.IPv6 with address fe80::6ef0:49ff:feb9:b17f. Jun 6 10:39:09 lolbox avahi-daemon[619]: New relevant interface eth0.IPv6 for mDNS. Jun 6 10:39:09 lolbox avahi-daemon[619]: Registering new address record for fe80::6ef0:49ff:feb9:b17f on eth0.*. Jun 6 10:39:10 lolbox dhclient: XMT: Solicit on eth0, interval 2180ms. Jun 6 10:39:10 lolbox dhclient: RCV: Advertise message on eth0 from fe80::120d:7fff:fe97:9d54. Jun 6 10:39:10 lolbox dhclient: IA_NA status code NoAddrsAvail. Jun 6 10:39:10 lolbox NetworkManager[862]: <info> (eth0): device state change: ip-config -> secondaries (reason 'none') [70 90 0] Jun 6 10:39:10 lolbox NetworkManager[862]: <info> Activation (eth0) Stage 5 of 5 (IPv4 Commit) complete. Jun 6 10:39:10 lolbox NetworkManager[862]: <info> (eth0): device state change: secondaries -> activated (reason 'none') [90 100 0] Jun 6 10:39:10 lolbox NetworkManager[862]: <info> NetworkManager state is now CONNECTED_GLOBAL Jun 6 10:39:10 lolbox NetworkManager[862]: <info> Policy set 'Wired connection 1' (eth0) as default for IPv4 routing and DNS. Jun 6 10:39:10 lolbox NetworkManager[862]: <info> Writing DNS information to /sbin/resolvconf Jun 6 10:39:10 lolbox dnsmasq[1362]: setting upstream servers from DBus Jun 6 10:39:10 lolbox dnsmasq[1362]: using nameserver 127.0.0.1#53 Jun 6 10:39:10 lolbox dnsmasq[1362]: using nameserver 193.150.193.150#53 Jun 6 10:39:10 lolbox dnsmasq[1362]: using nameserver 83.255.245.11#53 Jun 6 10:39:10 lolbox NetworkManager[862]: <info> Activation (eth0) successful, device activated. Jun 6 10:39:10 lolbox whoopsie[1133]: message repeated 2 times: [ offline] Jun 6 10:39:10 lolbox whoopsie[1133]: online Jun 6 10:39:10 lolbox ntpdate[13339]: Can't find host ntp.ubuntu.com: Name or service not known (-2) Jun 6 10:39:10 lolbox ntpdate[13339]: no servers can be used, exiting Jun 6 10:39:11 lolbox dnsmasq[1138]: reading /var/run/dnsmasq/resolv.conf Jun 6 10:39:11 lolbox dnsmasq[1138]: using nameserver 127.0.1.1#53 Jun 6 10:39:12 lolbox dhclient: XMT: Solicit on eth0, interval 4350ms. Jun 6 10:39:12 lolbox dhclient: RCV: Advertise message on eth0 from fe80::120d:7fff:fe97:9d54. Jun 6 10:39:12 lolbox dhclient: IA_NA status code NoAddrsAvail. Jun 6 10:39:16 lolbox dhclient: XMT: Solicit on eth0, interval 8740ms. Jun 6 10:39:16 lolbox dhclient: RCV: Advertise message on eth0 from fe80::120d:7fff:fe97:9d54. Jun 6 10:39:16 lolbox dhclient: IA_NA status code NoAddrsAvail. Jun 6 10:39:17 lolbox dnsmasq[1138]: Maximum number of concurrent DNS queries reached (max: 150) Jun 6 10:39:17 lolbox dnsmasq[1362]: Maximum number of concurrent DNS queries reached (max: 150) Jun 6 10:39:25 lolbox dhclient: XMT: Solicit on eth0, interval 17610ms. Jun 6 10:39:25 lolbox dhclient: RCV: Advertise message on eth0 from fe80::120d:7fff:fe97:9d54. Jun 6 10:39:25 lolbox dhclient: IA_NA status code NoAddrsAvail.

    Read the article

  • Injection with google guice does not work anymore after obfuscation with proguard

    - by sme
    Has anyone ever tried to combine the use of google guice with obfuscation (in particular proguard)? The obfuscated version of my code does not work with google guice as guice complains about missing type parameters. This information seems to be erased by the transformation step that proguard does, even when the relevant classes are excluded from the obfuscation. The stack trace looks like this: com.google.inject.CreationException: Guice creation errors: 1) Cannot inject a Provider that has no type parameter while locating com.google.inject.Provider for parameter 0 at de.repower.lvs.client.admin.user.administration.AdminUserCommonPanel.setPasswordPanelProvider(SourceFile:499) at de.repower.lvs.client.admin.user.administration.AdminUserCommonPanel.setPasswordPanelProvider(SourceFile:499) while locating de.repower.lvs.client.admin.user.administration.AdminUserCommonPanel for parameter 0 at de.repower.lvs.client.admin.user.administration.b.k.setParentPanel(SourceFile:65) at de.repower.lvs.client.admin.user.administration.b.k.setParentPanel(SourceFile:65) at de.repower.lvs.client.admin.user.administration.o.a(SourceFile:38) 2) Cannot inject a Provider that has no type parameter while locating com.google.inject.Provider for parameter 0 at de.repower.lvs.client.admin.user.administration.AdminUserCommonPanel.setWindTurbineAccessGroupProvider(SourceFile:509) at de.repower.lvs.client.admin.user.administration.AdminUserCommonPanel.setWindTurbineAccessGroupProvider(SourceFile:509) while locating de.repower.lvs.client.admin.user.administration.AdminUserCommonPanel for parameter 0 at de.repower.lvs.client.admin.user.administration.b.k.setParentPanel(SourceFile:65) at de.repower.lvs.client.admin.user.administration.b.k.setParentPanel(SourceFile:65) at de.repower.lvs.client.admin.user.administration.o.a(SourceFile:38) 2 errors at com.google.inject.internal.Errors.throwCreationExceptionIfErrorsExist(Errors.java:354) at com.google.inject.InjectorBuilder.initializeStatically(InjectorBuilder.java:152) at com.google.inject.InjectorBuilder.build(InjectorBuilder.java:105) at com.google.inject.Guice.createInjector(Guice.java:92) at com.google.inject.Guice.createInjector(Guice.java:69) at com.google.inject.Guice.createInjector(Guice.java:59) I tried to create a small example (without using guice) that seems to reproduce the problem: package de.repower.common; import java.lang.reflect.Method; import java.lang.reflect.ParameterizedType; import java.lang.reflect.Type; class SomeClass<S> { } public class ParameterizedTypeTest { public void someMethod(SomeClass<Integer> param) { System.out.println("value: " + param); System.setProperty("my.dummmy.property", "hallo"); } private static void checkParameterizedMethod(ParameterizedTypeTest testObject) { System.out.println("checking parameterized method ..."); Method[] methods = testObject.getClass().getMethods(); for (Method method : methods) { if (method.getName().equals("someMethod")) { System.out.println("Found method " + method.getName()); Type[] types = method.getGenericParameterTypes(); Type parameterType = types[0]; if (parameterType instanceof ParameterizedType) { Type parameterizedType = ((ParameterizedType) parameterType).getActualTypeArguments()[0]; System.out.println("Parameter: " + parameterizedType); System.out.println("Class: " + ((Class) parameterizedType).getName()); } else { System.out.println("Failed: type ist not instance of ParameterizedType"); } } } } public static void main(String[] args) { System.out.println("Starting ..."); try { ParameterizedTypeTest someInstance = new ParameterizedTypeTest(); checkParameterizedMethod(someInstance); } catch (SecurityException e) { e.printStackTrace(); } } } If you run this code unsbfuscated, the output looks like this: Starting ... checking parameterized method ... Found method someMethod Parameter: class java.lang.Integer Class: java.lang.Integer But running the version obfuscated with proguard yields: Starting ... checking parameterized method ... Found method someMethod Failed: type ist not instance of ParameterizedType These are the options I used for obfuscation: -injars classes_eclipse\methodTest.jar -outjars classes_eclipse\methodTestObfuscated.jar -libraryjars 'C:\Program Files\Java\jre6\lib\rt.jar' -dontskipnonpubliclibraryclasses -dontskipnonpubliclibraryclassmembers -dontshrink -printusage classes_eclipse\shrink.txt -dontoptimize -dontpreverify -verbose -keep class **.ParameterizedTypeTest.class { <fields>; <methods>; } -keep class ** { <fields>; <methods>; } # Keep - Applications. Keep all application classes, along with their 'main' # methods. -keepclasseswithmembers public class * { public static void main(java.lang.String[]); } # Also keep - Enumerations. Keep the special static methods that are required in # enumeration classes. -keepclassmembers enum * { public static **[] values(); public static ** valueOf(java.lang.String); } # Also keep - Database drivers. Keep all implementations of java.sql.Driver. -keep class * extends java.sql.Driver # Also keep - Swing UI L&F. Keep all extensions of javax.swing.plaf.ComponentUI, # along with the special 'createUI' method. -keep class * extends javax.swing.plaf.ComponentUI { public static javax.swing.plaf.ComponentUI createUI(javax.swing.JComponent); } # Keep names - Native method names. Keep all native class/method names. -keepclasseswithmembers,allowshrinking class * { native <methods>; } # Keep names - _class method names. Keep all .class method names. This may be # useful for libraries that will be obfuscated again with different obfuscators. -keepclassmembers,allowshrinking class * { java.lang.Class class$(java.lang.String); java.lang.Class class$(java.lang.String,boolean); } Does anyone have an idea of how to solve this (apart from the obvious workaround to put the relevant files into a seperate jar and not obfuscate it)? Best regards, Stefan

    Read the article

  • --log-slave-updates is OFF but some updates are still logged to the slave binary log?

    - by quanta
    MySQL version 5.5.14 According to the document, by the default, slave does not log to its binary log any updates that are received from a master server. Here are my config. on the slave: # egrep 'bin|slave' /etc/my.cnf relay-log=mysqld-relay-bin log-bin = /var/log/mysql/mysql-bin binlog-format=MIXED sync_binlog = 1 log-bin-trust-function-creators = 1 mysql> show global variables like 'log_slave%'; +-------------------+-------+ | Variable_name | Value | +-------------------+-------+ | log_slave_updates | OFF | +-------------------+-------+ 1 row in set (0.01 sec) mysql> select @@log_slave_updates; +---------------------+ | @@log_slave_updates | +---------------------+ | 0 | +---------------------+ 1 row in set (0.00 sec) but slave still logs the some changes to its binary logs, let's see the file size: -rw-rw---- 1 mysql mysql 37M Apr 1 01:00 /var/log/mysql/mysql-bin.001256 -rw-rw---- 1 mysql mysql 25M Apr 2 01:00 /var/log/mysql/mysql-bin.001257 -rw-rw---- 1 mysql mysql 46M Apr 3 01:00 /var/log/mysql/mysql-bin.001258 -rw-rw---- 1 mysql mysql 115M Apr 4 01:00 /var/log/mysql/mysql-bin.001259 -rw-rw---- 1 mysql mysql 105M Apr 4 18:54 /var/log/mysql/mysql-bin.001260 and the sample query when reading these binary files with mysqlbinlog utility: #120404 19:08:57 server id 3 end_log_pos 110324763 Query thread_id=382435 exec_time=0 error_code=0 SET TIMESTAMP=1333541337/*!*/; INSERT INTO norep_SplitValues VALUES ( NAME_CONST('cur_string',_utf8'118212' COLLATE 'utf8_general_ci')) /*!*/; # at 110324763 Did I miss something? Reply to @RolandoMySQLDBA: If replication brought this over, then the same query has to be in the relay logs. Please go find the relay log that has the INSERT query with the same TIMESTAMP (1333541337). There is no such query with the same TIMESTAMP in the relay logs. If you cannot find it in the relay logs, then look and see if Infobright is posting the INSERT query. In that instance, the INSERT should be recorded in the binary logs of the Slave. Looking more deeply into the binary logs, I see that almost of the queries are CREATE/INSERT/UPDATE/DROP "temporary" tables, something like this: # at 123873315 #120405 0:42:04 server id 3 end_log_pos 123873618 Query thread_id=395373 exec_time=0 error_code=0 SET TIMESTAMP=1333561324/*!*/; SET @@session.pseudo_thread_id=395373/*!*/; CREATE TEMPORARY TABLE `norep_tmpcampaign` ( `campaignid` INTEGER(11) NOT NULL DEFAULT '0' , `status` INTEGER(11) NOT NULL DEFAULT '0' , `updated` DATETIME, KEY `campaignid` (`campaignid`) )ENGINE=MEMORY /*!*/; # at 123873618 #120405 0:42:04 server id 3 end_log_pos 123873755 Query thread_id=395373 exec_time=0 error_code=0 SET TIMESTAMP=1333561324/*!*/; DROP TABLE IF EXISTS `norep_tmpcampaign1` /* generated by server */ "temporary" here means that they are dropped after calculation is done. I also tells the slave not to replicate any statement matches the norep_ wildcard pattern: replicate-wild-ignore-table=%.norep_% But there is an exception table in the binary logs: # at 123828094 #120405 0:37:21 server id 3 end_log_pos 123828495 Query thread_id=395209 exec_time=0 error_code=0 SET TIMESTAMP=1333561041/*!*/; INSERT INTO sessions (SessionId, ApplicationName, Created, Expires, LockDate, LockId, Timeout, Locked, SessionItems, Fla gs) Values('pgv2exo4y4vo4ccz44vwznu0', '/', '2012-04-05 00:37:21', '2012-04-05 00:57:21', '2012-04-05 00:37:21', 0, 20, 0, 'AwAAAP////8IdXNlcm5hbWUGdXNlcmlkCHBlcm1pdGlkAgAAAAQAAAAGAAAAAQABAAEA', 0) /*!*/; Description: mysql> desc reportingdb.sessions; +-----------------+------------------+------+-----+---------------------+-------+ | Field | Type | Null | Key | Default | Extra | +-----------------+------------------+------+-----+---------------------+-------+ | SessionId | varchar(64) | NO | PRI | | | | ApplicationName | varchar(255) | NO | | | | | Created | timestamp | NO | | 0000-00-00 00:00:00 | | | Expires | timestamp | NO | | 0000-00-00 00:00:00 | | | LockDate | timestamp | NO | | 0000-00-00 00:00:00 | | | LockId | int(11) unsigned | NO | | NULL | | | Timeout | int(11) unsigned | NO | | NULL | | | Locked | bit(1) | NO | | NULL | | | SessionItems | varchar(255) | YES | | NULL | | | Flags | int(11) | NO | | NULL | | +-----------------+------------------+------+-----+---------------------+-------+ I'm sure all these queries are posting by MySQL, not Infobright: $ mysql-ib -u root -p Enter password: Welcome to the MySQL monitor. Commands end with ; or \g. Your MySQL connection id is 48971 Server version: 5.1.40 build number (revision)=IB_4.0.5_r15240_15370(ice) (static) Type 'help;' or '\h' for help. Type '\c' to clear the current input statement. mysql> select * from information_schema.tables where table_name='sessions'; Empty set (0.02 sec) I've been trying some INSERT/UPDATE queries with testing tables on the master, it is copied to the relay logs, not binary logs on slave: # at 311664029 #120405 0:15:23 server id 1 end_log_pos 311664006 Query thread_id=10458250 exec_time=0 error_code=0 use testuser/*!*/; SET TIMESTAMP=1333559723/*!*/; update users set email2='[email protected]' where id=22 /*!*/; Pay attention to the server id, in the relay logs, server id is master's (1) and in the binary log, server id is slave's (3 in this case). Reply to @RolandoMySQLDBA: Thu Apr 5 10:06:00 ICT 2012 Run CREATE DATABASE quantatest; on the Master now, please. Tell me if CREATE DATABASE quantatest; showed up in the Slave's Binary Logs. As I said above: I've been trying some INSERT/UPDATE queries with testing tables on the master, it is copied to the relay logs, not binary logs and you can guess, IO thread copied it to the relay logs, not binary logs. #120405 10:07:25 server id 1 end_log_pos 347573819 Query thread_id=10480775 exec_time=0 error_code=0 SET TIMESTAMP=1333595245/*!*/; /*!\C latin1 *//*!*/; SET @@session.character_set_client=8,@@session.collation_connection=8,@@session.collation_server=8/*!*/; create database quantatest /*!*/; The question must probably change to: why some update queries still logged to the slave binary logs althrough --log-slave-updates is disabled? Where they come from? Here are few last: /*!*/; # at 27492197 #120405 10:12:45 server id 3 end_log_pos 27492370 Query thread_id=410353 exec_time=0 error_code=0 SET TIMESTAMP=1333595565/*!*/; CREATE TEMPORARY TABLE norep_SplitValues ( value VARCHAR(1000) NOT NULL ) ENGINE=MEMORY /*!*/; # at 27492370 #120405 10:12:45 server id 3 end_log_pos 27492445 Query thread_id=410353 exec_time=0 error_code=0 SET TIMESTAMP=1333595565/*!*/; BEGIN /*!*/; # at 27492445 #120405 10:12:45 server id 3 end_log_pos 27492619 Query thread_id=410353 exec_time=0 error_code=0 SET TIMESTAMP=1333595565/*!*/; INSERT INTO norep_SplitValues VALUES ( NAME_CONST('cur_string',_utf8'119577' COLLATE 'utf8_general_ci')) /*!*/; # at 27492619 #120405 10:12:45 server id 3 end_log_pos 27492695 Query thread_id=410353 exec_time=0 error_code=0 SET TIMESTAMP=1333595565/*!*/; COMMIT /*!*/; # at 27492918 #120405 10:12:46 server id 3 end_log_pos 27493115 Query thread_id=410353 exec_time=0 error_code=0 SET TIMESTAMP=1333595566/*!*/; SELECT `reportingdb`.`selfserving_get_locationad`(_utf8'3' COLLATE 'utf8_general_ci',_utf8'' COLLATE 'utf8_general_ci') /*!*/; # at 27493199 #120405 10:12:46 server id 3 end_log_pos 27493353 Query thread_id=410353 exec_time=0 error_code=0 SET TIMESTAMP=1333595566/*!*/; /*!\C utf8 *//*!*/; SET @@session.character_set_client=33,@@session.collation_connection=33,@@session.collation_server=8/*!*/; DROP TEMPORARY TABLE IF EXISTS `norep_SplitValues` /* generated by server */ /*!*/;

    Read the article

  • Finding a person in the forest

    - by PointsToShare
    © 2011 By: Dov Trietsch. All rights reserved finding a person in the forest or Limiting the AD result in SharePoint People Picker There are times when we need to limit the SharePoint audience of certain farms or servers or site collections to a particular audience. One of my experiences involved limiting access to US citizens, another to a particular location. Now, most of us – your humble servant included – are not Active Directory experts – but we must be able to handle the “audience restrictions” as required. So here is how it’s done in a nutshell. Important note. Not all could be done in PowerShell (at least not yet)! There are no Windows PowerShell commands to configure People Picker. The stsadm command is: stsadm -o setproperty -pn peoplepicker-searchadcustomquery -pv ADQuery –url http://somethingOrOther Note the long-hyphenated property name. Now to filling the ADQuery.   LDAP Query in a nutshell Syntax LDAP is no older than SQL and an LDAP query is actually a query against the LDAP Database. LDAP attributes are the equivalent of Database columns, so why do we have to learn a new query language? Beats me! But we must, so here it is. The syntax of an LDAP query string is made of individual statements with relational operators including: = Equal <= Lower than or equal >= Greater than or equal… and memberOf – a group membership. ! Not * Wildcard Equal and memberOf are the most commonly used. Checking for absence uses the ! – not and the * - wildcard Example: (SN=Grant) All whose last name – SurName – is Grant Example: (!(SN=Grant)) All except Grant Example: (!(SN=*)) all where there is no SurName i.e SurName is absent (probably Rappers). Example: (CN=MyGroup) Common Name is MyGroup.  Example: (GN=J*) all the Given Names that start with J (JJ, Jane, Jon, John, etc.) The cryptic SN, CN, GN, etc. are attributes and more about them later All the queries are enclosed in parentheses (Query). Complex queries are comprised of sets that are in AND or OR conditions. AND is denoted by the ampersand (&) and the OR is denoted by the vertical pipe (|). The general syntax is that of the Prefix polish notation where the operand precedes the variables. E.g +ab is the sum of a and b. In an LDAP query (&(A)(B)) will garner the objects for which both A and B are true. In an LDAP query (&(A)(B)(C)) will garner the objects for which A, B and C are true. There’s no limit to the number of conditions. In an LDAP query (|(A)(B)) will garner the objects for which either A or B are true. In an LDAP query (|(A)(B)(C)) will garner the objects for which at least one of A, B and C is true. There’s no limit to the number of conditions. More complex queries have both types of conditions and the parentheses determine the order of operations. Attributes Now let’s get into the SN, CN, GN, and other attributes of the query SN – is the SurName (last name) GN – is the Given Name (first name) CN – is the Common Name, usually GN followed by SN OU – is an Organization Unit such as division, department etc. DC – is a Domain Content in the AD forest l – lower case ‘L’ stands for location. Jerusalem anybody? Or Katmandu. UPN – User Principal Name, is usually the first part of an email address. By nature it is unique in the forest. Most systems set the UPN to be the first initial followed by the SN of the person involved. Some limit the total to 8 characters. If we have many ‘jsmith’ we have to somehow distinguish them from each other. DN – is the distinguished name – a name unique to AD forest in which it lives. Usually it’s a CN with some domain or group distinguishers. DN is important in conjunction with the memberOf relation. Groups have stricter requirement. Each group has to have a unique name - its CN and it has to be unique regardless of its place. See more below. All of the attributes are case insensitive. CN, cn, Cn, and cN are identical. objectCategory is an element that requires special consideration. AD contains many different object like computers, printers, and of course people and groups. In the queries below, we’re limiting our search to people (person). Putting it altogether Let’s get a list of all the Johns in the SPAdmin group of the Jerusalem that local domain. (&(objectCategory=person)(memberOf=cn=SPAdmin,ou=Jerusalem,dc=local)) The memberOf=cn=SPAdmin uses the cn (Common Name) of the SPAdmin group. This is how the memberOf relation is used. ‘SPAdmin’ is actually the DN of the group. Also the memberOf relation does not allow wild cards (*) in the group name. Also, you are limited to at most one ‘OU’ entry. Let’s add Marvin Minsky to the search above. |(&(objectCategory=person)(memberOf=cn=SPAdmin,ou=Jerusalem,dc=local))(CN=Marvin Minsky) Here I added the or pipeline at the beginning of the query and put the CN requirement for Minsky at the end. Note that if Marvin was already in the prior result, he’s not going to be listed twice. One last note: You may see a dryer but more complete list of attributes rules and examples in: http://www.tek-tips.com/faqs.cfm?fid=5667 And finally (thus negating the claim that my previous note was last), to the best of my knowledge there are 3 more ways to limit the audience. One is to use the peoplepicker-searchadcustomfilter property using the same ADQuery. This works only in SP1 and above. The second is to limit the search to users within this particular site collection – the property name is peoplepicker-onlysearchwithinsitecollection and the value is yes (-pv yes) And the third is –pn peoplepicker-serviceaccountdirectorypaths –pv “OU=ou1,DC=dc1…..” Again you are limited to at most one ‘OU’ phrase – no OU=ou1,OU=ou2… And now the real end. The main property discussed in this sprawling and seemingly endless monogram – peoplepicker-searchadcustomquery - is the most general way of getting the job done. Here are a few examples of command lines that worked and some that didn’t. Can you see why? C:\Program Files\Common Files\Microsoft Shared\Web Server Extensions\12\BIN>stsa dm -o setproperty -url http://somethingOrOther -pn peoplepicker-searchadcustomfi lter -pv (Title=David) Operation completed successfully. C:\Program Files\Common Files\Microsoft Shared\Web Server Extensions\12\BIN>stsa dm -o setproperty -url http://somethingOrOther -pn peoplepicker-searchadcustomfi lter -pv (!Title=David) Operation completed successfully. C:\Program Files\Common Files\Microsoft Shared\Web Server Extensions\12\BIN>stsa dm -o setproperty -url http://somethingOrOther -pn peoplepicker-searchadcustomfi lter -pv (OU=OURealName,OU=OUMid,OU=OUTop,DC=TopDC,DC=MidDC,DC=BottomDC) Command line error. Too many OUs C:\Program Files\Common Files\Microsoft Shared\Web Server Extensions\12\BIN>stsa dm -o setproperty -url http://somethingOrOther -pn peoplepicker-searchadcustomfi lter -pv (OU=OURealName) Operation completed successfully. C:\Program Files\Common Files\Microsoft Shared\Web Server Extensions\12\BIN>stsa dm -o setproperty -url http://somethingOrOther -pn peoplepicker-searchadcustomfi lter -pv (DC=TopDC,DC=MidDC,DC=BottomDC) Operation completed successfully. C:\Program Files\Common Files\Microsoft Shared\Web Server Extensions\12\BIN>stsa dm -o setproperty -url http://somethingOrOther -pn peoplepicker-searchadcustomfi lter -pv (OU=OURealName,DC=TopDC,DC=MidDC,DC=BottomDC) Operation completed successfully.   That’s all folks!

    Read the article

  • SQL SERVER – Weekly Series – Memory Lane – #048

    - 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 Order of Result Set of SELECT Statement on Clustered Indexed Table When ORDER BY is Not Used Above theory is true in most of the cases. However SQL Server does not use that logic when returning the resultset. SQL Server always returns the resultset which it can return fastest.In most of the cases the resultset which can be returned fastest is the resultset which is returned using clustered index. Effect of TRANSACTION on Local Variable – After ROLLBACK and After COMMIT One of the Jr. Developer asked me this question (What will be the Effect of TRANSACTION on Local Variable – After ROLLBACK and After COMMIT?) while I was rushing to an important meeting. I was getting late so I asked him to talk with his Application Tech Lead. When I came back from meeting both of them were looking for me. They said they are confused. I quickly wrote down following example for them. 2008 SQL SERVER – Guidelines and Coding Standards Complete List Download Coding standards and guidelines are very important for any developer on the path of a successful career. A coding standard is a set of guidelines, rules and regulations on how to write code. Coding standards should be flexible enough or should take care of the situation where they should not prevent best practices for coding. They are basically the guidelines that one should follow for better understanding. Download Guidelines and Coding Standards complete List Download Get Answer in Float When Dividing of Two Integer Many times we have requirements of some calculations amongst different fields in Tables. One of the software developers here was trying to calculate some fields having integer values and divide it which gave incorrect results in integer where accurate results including decimals was expected. Puzzle – Computed Columns Datatype Explanation SQL Server automatically does a cast to the data type having the highest precedence. So the result of INT and INT will be INT, but INT and FLOAT will be FLOAT because FLOAT has a higher precedence. If you want a different data type, you need to do an EXPLICIT cast. Renaming SP is Not Good Idea – Renaming Stored Procedure Does Not Update sys.procedures I have written many articles about renaming a tables, columns and procedures SQL SERVER – How to Rename a Column Name or Table Name, here I found something interesting about renaming the stored procedures and felt like sharing it with you all. The interesting fact is that when we rename a stored procedure using SP_Rename command, the Stored Procedure is successfully renamed. But when we try to test the procedure using sp_helptext, the procedure will be having the old name instead of new names. 2009 Insert Values of Stored Procedure in Table – Use Table Valued Function It is clear from the result set that , where I have converted stored procedure logic into the table valued function, is much better in terms of logic as it saves a large number of operations. However, this option should be used carefully. The performance of the stored procedure is “usually” better than that of functions. Interesting Observation – Index on Index View Used in Similar Query Recently, I was working on an optimization project for one of the largest organizations. While working on one of the queries, we came across a very interesting observation. We found that there was a query on the base table and when the query was run, it used the index, which did not exist in the base table. On careful examination, we found that the query was using the index that was on another view. This was very interesting as I have personally never experienced a scenario like this. In simple words, “Query on the base table can use the index created on the indexed view of the same base table.” Interesting Observation – Execution Plan and Results of Aggregate Concatenation Queries Working with SQL Server has never seemed to be monotonous – no matter how long one has worked with it. Quite often, I come across some excellent comments that I feel like acknowledging them as blog posts. Recently, I wrote an article on SQL SERVER – Execution Plan and Results of Aggregate Concatenation Queries Depend Upon Expression Location, which is well received in the community. 2010 I encourage all of you to go through complete series and write your own on the subject. If you write an article and send it to me, I will publish it on this blog with due credit to you. If you write on your own blog, I will update this blog post pointing to your blog post. SQL SERVER – ORDER BY Does Not Work – Limitation of the View 1 SQL SERVER – Adding Column is Expensive by Joining Table Outside View – Limitation of the View 2 SQL SERVER – Index Created on View not Used Often – Limitation of the View 3 SQL SERVER – SELECT * and Adding Column Issue in View – Limitation of the View 4 SQL SERVER – COUNT(*) Not Allowed but COUNT_BIG(*) Allowed – Limitation of the View 5 SQL SERVER – UNION Not Allowed but OR Allowed in Index View – Limitation of the View 6 SQL SERVER – Cross Database Queries Not Allowed in Indexed View – Limitation of the View 7 SQL SERVER – Outer Join Not Allowed in Indexed Views – Limitation of the View 8 SQL SERVER – SELF JOIN Not Allowed in Indexed View – Limitation of the View 9 SQL SERVER – Keywords View Definition Must Not Contain for Indexed View – Limitation of the View 10 SQL SERVER – View Over the View Not Possible with Index View – Limitations of the View 11 2011 Startup Parameters Easy to Configure If you are a regular reader of this blog, you must be aware that I have written about SQL Server Denali recently. Here is the quickest way to reach into the screen where we can change the startup parameters. Go to SQL Server Configuration Manager >> SQL Server Services >> Right Click on the Server >> Properties >> Startup Parameters 2012 Validating Unique Columnname Across Whole Database I sometimes come across very strange requirements and often I do not receive a proper explanation of the same. Here is the one of those examples. For example “Our business requirement is when we add new column we want it unique across current database.” Read the solution to this strange request in this blog post. Excel Losing Decimal Values When Value Pasted from SSMS ResultSet It is very common when users are coping the resultset to Excel, the floating point or decimals are missed. The solution is very much simple and it requires a small adjustment in the Excel. By default Excel is very smart and when it detects the value which is getting pasted is numeric it changes the column format to accommodate that. Basic Calculation and PEMDAS Order of Operation Read this interesting blog post for fantastic conversation about the subject. Copy Column Headers from Resultset – SQL in Sixty Seconds #027 – Video http://www.youtube.com/watch?v=x_-3tLqTRv0 Delete From Multiple Table – Update Multiple Table in Single Statement There are two questions which I get every single day multiple times. In my gmail, I have created standard canned reply for them. Let us see the questions here. I want to delete from multiple table in a single statement how will I do it? I want to update multiple table in a single statement how will I do it? Read the answer in the blog post. 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

    Read the article

  • SQL SERVER – Weekly Series – Memory Lane – #050

    - 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 Executing Remote Stored Procedure – Calling Stored Procedure on Linked Server In this example we see two different methods of how to call Stored Procedures remotely.  Connection Property of SQL Server Management Studio SSMS A very simple example of the how to build connection properties for SQL Server with the help of SSMS. Sample Example of RANKING Functions – ROW_NUMBER, RANK, DENSE_RANK, NTILE SQL Server has a total of 4 ranking functions. Ranking functions return a ranking value for each row in a partition. All the ranking functions are non-deterministic. T-SQL Script to Add Clustered Primary Key Jr. DBA asked me three times in a day, how to create Clustered Primary Key. I gave him following sample example. That was the last time he asked “How to create Clustered Primary Key to table?” 2008 2008 – TRIM() Function – User Defined Function SQL Server does not have functions which can trim leading or trailing spaces of any string at the same time. SQL does have LTRIM() and RTRIM() which can trim leading and trailing spaces respectively. SQL Server 2008 also does not have TRIM() function. User can easily use LTRIM() and RTRIM() together and simulate TRIM() functionality. http://www.youtube.com/watch?v=1-hhApy6MHM 2009 Earlier I have written two different articles on the subject Remove Bookmark Lookup. This article is as part 3 of original article. Please read the first two articles here before continuing reading this article. Query Optimization – Remove Bookmark Lookup – Remove RID Lookup – Remove Key Lookup Query Optimization – Remove Bookmark Lookup – Remove RID Lookup – Remove Key Lookup – Part 2 Query Optimization – Remove Bookmark Lookup – Remove RID Lookup – Remove Key Lookup – Part 3 Interesting Observation – Query Hint – FORCE ORDER SQL Server never stops to amaze me. As regular readers of this blog already know that besides conducting corporate training, I work on large-scale projects on query optimizations and server tuning projects. In one of the recent projects, I have noticed that a Junior Database Developer used the query hint Force Order; when I asked for details, I found out that the basic concept was not properly understood by him. Queries Waiting for Memory Allocation to Execute In one of the recent projects, I was asked to create a report of queries that are waiting for memory allocation. The reason was that we were doubtful regarding whether the memory was sufficient for the application. The following query can be useful in similar cases. Queries that do not have to wait on a memory grant will not appear in the result set of following query. 2010 Quickest Way to Identify Blocking Query and Resolution – Dirty Solution As the title suggests, this is quite a dirty solution; it’s not as elegant as you expect. However, it works totally fine. Simple Explanation of Data Type Precedence While I was working on creating a question for SQL SERVER – SQL Quiz – The View, The Table and The Clustered Index Confusion, I had actually created yet another question along with this question. However, I felt that the one which is posted on the SQL Quiz is much better than this one because what makes that more challenging question is that it has a multiple answer. Encrypted Stored Procedure and Activity Monitor I recently had received questionable if any stored procedure is encrypted can we see its definition in Activity Monitor.Answer is - No. Let us do a quick test. Let us create following Stored Procedure and then launch the Activity Monitor and check the text. Indexed View always Use Index on Table A single table can have maximum 249 non clustered indexes and 1 clustered index. In SQL Server 2008, a single table can have maximum 999 non clustered indexes and 1 clustered index. It is widely believed that a table can have only 1 clustered index, and this belief is true. I have some questions for all of you. Let us assume that I am creating view from the table itself and then create a clustered index on it. In my view, I am selecting the complete table itself. 2011 Detecting Database Case Sensitive Property using fn_helpcollations() I received a question on how to determine the case sensitivity of the database. The quick answer to this is to identify the collation of the database and check the properties of the collation. I have previously written how one can identify database collation. Once you have figured out the collation of the database, you can put that in the WHERE condition of the following T-SQL and then check the case sensitivity from the description. Server Side Paging in SQL Server CE (Compact Edition) SQL Server Denali is coming up with new T-SQL of Paging. I have written about the same earlier.SQL SERVER – Server Side Paging in SQL Server Denali – A Better Alternative,  SQL SERVER – Server Side Paging in SQL Server Denali Performance Comparison, SQL SERVER – Server Side Paging in SQL Server Denali – Part2 What is very interesting is that SQL Server CE 4.0 have the same feature introduced. Here is the quick example of the same. To run the script in the example, you will have to do installWebmatrix 4.0 and download sample database. Once done you can run following script. Why I am Going to Attend PASS Summit Unite 2011 The four-day event will be marked by a lot of learning, sharing, and networking, which will help me increase both my knowledge and contacts. Every year, PASS Summit provides me a golden opportunity to build my network as well as to identify and meet potential customers or employees. 2012 Manage Help Settings – CTRL + ALT + F1 This is very interesting read as my daughter once accidently came across a screen in SQL Server Management Studio. It took me 2-3 minutes to figure out how she has created the same screen. Recover the Accidentally Renamed Table “I accidentally renamed table in my SSMS. I was scrolling very fast and I made mistakes. It was either because I double clicked or clicked on F2 (shortcut key for renaming). However, I have made the mistake and now I have no idea how to fix this. If you have renamed the table, I think you pretty much is out of luck. Here are few things which you can do which can give you an idea about what your table name can be if you are lucky. Identify Numbers of Non Clustered Index on Tables for Entire Database Here is the script which will give you numbers of non clustered indexes on any table in entire database. Identify Most Resource Intensive Queries – SQL in Sixty Seconds #029 – Video Here is the complete complete script which I have used in the SQL in Sixty Seconds Video. Thanks Harsh for important Tip in the comment. http://www.youtube.com/watch?v=3kDHC_Tjrns Advanced Data Quality Services with Melissa Data – Azure Data Market For the purposes of the review, I used a database I had in an Excel spreadsheet with name and address information. Upon a cursory inspection, there are miscellaneous problems with these records; some addresses are missing ZIP codes, others missing a city, and some records are slightly misspelled or have unparsed suites. With DQS, I can easily add a knowledge base to help standardize my values, such as for state abbreviations. But how do I know that my address is correct? 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

    Read the article

  • Query optimization using composite indexes

    - by xmarch
    Many times, during the process of creating a new Coherence application, developers do not pay attention to the way cache queries are constructed; they only check that these queries comply with functional specs. Later, performance testing shows that these perform poorly and it is then when developers start working on improvements until the non-functional performance requirements are met. This post describes the optimization process of a real-life scenario, where using a composite attribute index has brought a radical improvement in query execution times.  The execution times went down from 4 seconds to 2 milliseconds! E-commerce solution based on Oracle ATG – Endeca In the context of a new e-commerce solution based on Oracle ATG – Endeca, Oracle Coherence has been used to calculate and store SKU prices. In this architecture, a Coherence cache stores the final SKU prices used for Endeca baseline indexing. Each SKU price is calculated from a base SKU price and a series of calculations based on information from corporate global discounts. Corporate global discounts information is stored in an auxiliary Coherence cache with over 800.000 entries. In particular, to obtain each price the process needs to execute six queries over the global discount cache. After the implementation was finished, we discovered that the most expensive steps in the price calculation discount process were the global discounts cache query. This query has 10 parameters and is executed 6 times for each SKU price calculation. The steps taken to optimise this query are described below; Starting point Initial query was: String filter = "levelId = :iLevelId AND  salesCompanyId = :iSalesCompanyId AND salesChannelId = :iSalesChannelId "+ "AND departmentId = :iDepartmentId AND familyId = :iFamilyId AND brand = :iBrand AND manufacturer = :iManufacturer "+ "AND areaId = :iAreaId AND endDate >=  :iEndDate AND startDate <= :iStartDate"; Map<String, Object> params = new HashMap<String, Object>(10); // Fill all parameters. params.put("iLevelId", xxxx); // Executing filter. Filter globalDiscountsFilter = QueryHelper.createFilter(filter, params); NamedCache globalDiscountsCache = CacheFactory.getCache(CacheConstants.GLOBAL_DISCOUNTS_CACHE_NAME); Set applicableDiscounts = globalDiscountsCache.entrySet(globalDiscountsFilter); With the small dataset used for development the cache queries performed very well. However, when carrying out performance testing with a real-world sample size of 800,000 entries, each query execution was taking more than 4 seconds. First round of optimizations The first optimisation step was the creation of separate Coherence index for each of the 10 attributes used by the filter. This avoided object deserialization while executing the query. Each index was created as follows: globalDiscountsCache.addIndex(new ReflectionExtractor("getXXX" ) , false, null); After adding these indexes the query execution time was reduced to between 450 ms and 1s. However, these execution times were still not good enough.  Second round of optimizations In this optimisation phase a Coherence query explain plan was used to identify how many entires each index reduced the results set by, along with the cost in ms of executing that part of the query. Though the explain plan showed that all the indexes for the query were being used, it also showed that the ordering of the query parameters was "sub-optimal".  Parameters associated to object attributes with high-cardinality should appear at the beginning of the filter, or more specifically, the attributes that filters out the highest of number records should be placed at the beginning. But examining corporate global discount data we realized that depending on the values of the parameters used in the query the “good” order for the attributes was different. In particular, if the attributes brand and family had specific values it was more optimal to have a different query changing the order of the attributes. Ultimately, we ended up with three different optimal variants of the query that were used in its relevant cases: String filter = "brand = :iBrand AND familyId = :iFamilyId AND departmentId = :iDepartmentId AND levelId = :iLevelId "+ "AND manufacturer = :iManufacturer AND endDate >= :iEndDate AND salesCompanyId = :iSalesCompanyId "+ "AND areaId = :iAreaId AND salesChannelId = :iSalesChannelId AND startDate <= :iStartDate"; String filter = "familyId = :iFamilyId AND departmentId = :iDepartmentId AND levelId = :iLevelId AND brand = :iBrand "+ "AND manufacturer = :iManufacturer AND endDate >=  :iEndDate AND salesCompanyId = :iSalesCompanyId "+ "AND areaId = :iAreaId  AND salesChannelId = :iSalesChannelId AND startDate <= :iStartDate"; String filter = "brand = :iBrand AND departmentId = :iDepartmentId AND familyId = :iFamilyId AND levelId = :iLevelId "+ "AND manufacturer = :iManufacturer AND endDate >= :iEndDate AND salesCompanyId = :iSalesCompanyId "+ "AND areaId = :iAreaId AND salesChannelId = :iSalesChannelId AND startDate <= :iStartDate"; Using the appropriate query depending on the value of brand and family parameters the query execution time dropped to between 100 ms and 150 ms. But these these execution times were still not good enough and the solution was cumbersome. Third and last round of optimizations The third and final optimization was to introduce a composite index. However, this did mean that it was not possible to use the Coherence Query Language (CohQL), as composite indexes are not currently supporte in CohQL. As the original query had 8 parameters using EqualsFilter, 1 using GreaterEqualsFilter and 1 using LessEqualsFilter, the composite index was built for the 8 attributes using EqualsFilter. The final query had an EqualsFilter for the multiple extractor, a GreaterEqualsFilter and a LessEqualsFilter for the 2 remaining attributes.  All individual indexes were dropped except the ones being used for LessEqualsFilter and GreaterEqualsFilter. We were now running in an scenario with an 8-attributes composite filter and 2 single attribute filters. The composite index created was as follows: ValueExtractor[] ve = { new ReflectionExtractor("getSalesChannelId" ), new ReflectionExtractor("getLevelId" ),    new ReflectionExtractor("getAreaId" ), new ReflectionExtractor("getDepartmentId" ),    new ReflectionExtractor("getFamilyId" ), new ReflectionExtractor("getManufacturer" ),    new ReflectionExtractor("getBrand" ), new ReflectionExtractor("getSalesCompanyId" )}; MultiExtractor me = new MultiExtractor(ve); NamedCache globalDiscountsCache = CacheFactory.getCache(CacheConstants.GLOBAL_DISCOUNTS_CACHE_NAME); globalDiscountsCache.addIndex(me, false, null); And the final query was: ValueExtractor[] ve = { new ReflectionExtractor("getSalesChannelId" ), new ReflectionExtractor("getLevelId" ),    new ReflectionExtractor("getAreaId" ), new ReflectionExtractor("getDepartmentId" ),    new ReflectionExtractor("getFamilyId" ), new ReflectionExtractor("getManufacturer" ),    new ReflectionExtractor("getBrand" ), new ReflectionExtractor("getSalesCompanyId" )}; MultiExtractor me = new MultiExtractor(ve); // Fill composite parameters.String SalesCompanyId = xxxx;...AndFilter composite = new AndFilter(new EqualsFilter(me,                   Arrays.asList(iSalesChannelId, iLevelId, iAreaId, iDepartmentId, iFamilyId, iManufacturer, iBrand, SalesCompanyId)),                                     new GreaterEqualsFilter(new ReflectionExtractor("getEndDate" ), iEndDate)); AndFilter finalFilter = new AndFilter(composite, new LessEqualsFilter(new ReflectionExtractor("getStartDate" ), iStartDate)); NamedCache globalDiscountsCache = CacheFactory.getCache(CacheConstants.GLOBAL_DISCOUNTS_CACHE_NAME); Set applicableDiscounts = globalDiscountsCache.entrySet(finalFilter);      Using this composite index the query improved dramatically and the execution time dropped to between 2 ms and  4 ms.  These execution times completely met the non-functional performance requirements . It should be noticed than when using the composite index the order of the attributes inside the ValueExtractor was not relevant.

    Read the article

  • “Query cost (relative to the batch)” <> Query cost relative to batch

    - by Dave Ballantyne
    OK, so that is quite a contradictory title, but unfortunately it is true that a common misconception is that the query with the highest percentage relative to batch is the worst performing.  Simply put, it is a lie, or more accurately we dont understand what these figures mean. Consider the two below simple queries: SELECT * FROM Person.BusinessEntity JOIN Person.BusinessEntityAddress ON Person.BusinessEntity.BusinessEntityID = Person.BusinessEntityAddress.BusinessEntityID go SELECT * FROM Sales.SalesOrderDetail JOIN Sales.SalesOrderHeader ON Sales.SalesOrderDetail.SalesOrderID = Sales.SalesOrderHeader.SalesOrderID After executing these and looking at the plans, I see this : So, a 13% / 87% split ,  but 13% / 87% of WHAT ? CPU ? Duration ? Reads ? Writes ? or some magical weighted algorithm ?  In a Profiler trace of the two we can find the metrics we are interested in. CPU and duration are well out but what about reads (210 and 1935)? To save you doing the maths, though you are more than welcome to, that’s a 90.2% / 9.8% split.  Close, but no cigar. Lets try a different tact.  Looking at the execution plan the “Estimated Subtree cost” of query 1 is 0.29449 and query 2 its 1.96596.  Again to save you the maths that works out to 13.03% and 86.97%, round those and thats the figures we are after.  But, what is the worrying word there ? “Estimated”.  So these are not “actual”  execution costs,  but what’s the problem in comparing the estimated costs to derive a meaning of “Most Costly”.  Well, in the case of simple queries such as the above , probably not a lot.  In more complicated queries , a fair bit. By modifying the second query to also show the total number of lines on each order SELECT *,COUNT(*) OVER (PARTITION BY Sales.SalesOrderDetail.SalesOrderID) FROM Sales.SalesOrderDetail JOIN Sales.SalesOrderHeader ON Sales.SalesOrderDetail.SalesOrderID = Sales.SalesOrderHeader.SalesOrderID The split in percentages is now 6% / 94% and the profiler metrics are : Even more of a discrepancy. Estimates can be out with actuals for a whole host of reasons,  scalar UDF’s are a particular bug bear of mine and in-fact the cost of a udf call is entirely hidden inside the execution plan.  It always estimates to 0 (well, a very small number). Take for instance the following udf Create Function dbo.udfSumSalesForCustomer(@CustomerId integer) returns money as begin Declare @Sum money Select @Sum= SUM(SalesOrderHeader.TotalDue) from Sales.SalesOrderHeader where CustomerID = @CustomerId return @Sum end If we have two statements , one that fires the udf and another that doesn't: Select CustomerID from Sales.Customer order by CustomerID go Select CustomerID,dbo.udfSumSalesForCustomer(Customer.CustomerID) from Sales.Customer order by CustomerID The costs relative to batch is a 50/50 split, but the has to be an actual cost of firing the udf. Indeed profiler shows us : No where even remotely near 50/50!!!! Moving forward to window framing functionality in SQL Server 2012 the optimizer sees ROWS and RANGE ( see here for their functional differences) as the same ‘cost’ too SELECT SalesOrderDetailID,SalesOrderId, SUM(LineTotal) OVER(PARTITION BY salesorderid ORDER BY Salesorderdetailid RANGE unbounded preceding) from Sales.SalesOrderdetail go SELECT SalesOrderDetailID,SalesOrderId, SUM(LineTotal) OVER(PARTITION BY salesorderid ORDER BY Salesorderdetailid Rows unbounded preceding) from Sales.SalesOrderdetail By now it wont be a great display to show you the Profiler trace reads a *tiny* bit different. So moral of the story, Percentage relative to batch can give a rough ‘finger in the air’ measurement, but dont rely on it as fact.

    Read the article

  • More SQL Smells

    - by Nick Harrison
    Let's continue exploring some of the SQL Smells from Phil's list. He has been putting together. Datatype mis-matches in predicates that rely on implicit conversion.(Plamen Ratchev) This is a great example poking holes in the whole theory of "If it works it's not broken" Queries will this probably will generally work and give the correct response. In fact, without careful analysis, you probably may be completely oblivious that there is even a problem. This subtle little problem will needlessly complicate queries and slow them down regardless of the indexes applied. Consider this example: CREATE TABLE [dbo].[Page](     [PageId] [int] IDENTITY(1,1) NOT NULL,     [Title] [varchar](75) NOT NULL,     [Sequence] [int] NOT NULL,     [ThemeId] [int] NOT NULL,     [CustomCss] [text] NOT NULL,     [CustomScript] [text] NOT NULL,     [PageGroupId] [int] NOT NULL;  CREATE PROCEDURE PageSelectBySequence ( @sequenceMin smallint , @sequenceMax smallint ) AS BEGIN SELECT [PageId] , [Title] , [Sequence] , [ThemeId] , [CustomCss] , [CustomScript] , [PageGroupId] FROM [CMS].[dbo].[Page] WHERE Sequence BETWEEN @sequenceMin AND @SequenceMax END  Note that the Sequence column is defined as int while the sequence parameter is defined as a small int. The problem is that the database may have to do a lot of type conversions to evaluate the query. In some cases, this may even negate the indexes that you have in place. Using Correlated subqueries instead of a join   (Dave_Levy/ Plamen Ratchev) There are two main problems here. The first is a little subjective, since this is a non-standard way of expressing the query, it is harder to understand. The other problem is much more objective and potentially problematic. You are taking much of the control away from the optimizer. Written properly, such a query may well out perform a corresponding query written with traditional joins. More likely than not, performance will degrade. Whenever you assume that you know better than the optimizer, you will most likely be wrong. This is the fundmental problem with any hint. Consider a query like this:  SELECT Page.Title , Page.Sequence , Page.ThemeId , Page.CustomCss , Page.CustomScript , PageEffectParams.Name , PageEffectParams.Value , ( SELECT EffectName FROM dbo.Effect WHERE EffectId = dbo.PageEffects.EffectId ) AS EffectName FROM Page INNER JOIN PageEffect ON Page.PageId = PageEffects.PageId INNER JOIN PageEffectParam ON PageEffects.PageEffectId = PageEffectParams.PageEffectId  This can and should be written as:  SELECT Page.Title , Page.Sequence , Page.ThemeId , Page.CustomCss , Page.CustomScript , PageEffectParams.Name , PageEffectParams.Value , EffectName FROM Page INNER JOIN PageEffect ON Page.PageId = PageEffects.PageId INNER JOIN PageEffectParam ON PageEffects.PageEffectId = PageEffectParams.PageEffectId INNER JOIN dbo.Effect ON dbo.Effects.EffectId = dbo.PageEffects.EffectId  The correlated query may just as easily show up in the where clause. It's not a good idea in the select clause or the where clause. Few or No comments. This one is a bit more complicated and controversial. All comments are not created equal. Some comments are helpful and need to be included. Other comments are not necessary and may indicate a problem. I tend to follow the rule of thumb that comments that explain why are good. Comments that explain how are bad. Many people may be shocked to hear the idea of a bad comment, but hear me out. If a comment is needed to explain what is going on or how it works, the logic is too complex and needs to be simplified. Comments that explain why are good. Comments may explain why the sql is needed are good. Comments that explain where the sql is used are good. Comments that explain how tables are related should not be needed if the sql is well written. If they are needed, you need to consider reworking the sql or simplify your data model. Use of functions in a WHERE clause. (Anil Das) Calling a function in the where clause will often negate the indexing strategy. The function will be called for every record considered. This will often a force a full table scan on the tables affected. Calling a function will not guarantee that there is a full table scan, but there is a good chance that it will. If you find that you often need to write queries using a particular function, you may need to add a column to the table that has the function already applied.

    Read the article

< Previous Page | 41 42 43 44 45 46 47 48 49 50 51 52  | Next Page >