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  • How to correctly configure DNS for Icelandic domains and Plesk

    - by Leonard Challis
    I have a domain registered with ISNIC (domain.is). They only let you set nameservers that pass their requirements. I've been told it's this requirement that I need to fix: Nameserver must be consistently registered in DNS, i.e. its own A resource record must be available and a corresponding PTR resource record as well. I allocated two new IP addresses from my server host and at that point set their PTR records to ns0.domain.is and ns1.domain.is. After that I created two A records for that domain in Plesk, again ns0. and ns2.domain.is with their respective IPs. Next, I went to the ISNIC page to register my nameservers, along with their IP addresses I'd allocated and this worked perfectly for both without error. So the final job was to set the nameservers for the domain via ISNIC's control panel, however when I try, I'm getting this error: Test results for "NS0.DOMAIN.IS": The nameserver ns1.vps123.vpsprovider.com is not consistently registered in DNS (ns1.vps123.vpsprovider.com => 1123.123.123.123 => vps123.vpsprovider.com) The nameserver ns0.vps123.vpsprovider.com is not consistently registered in DNS (ns0.vps123.vpsprovider.com => 1123.123.123.123 => vps123.vpsprovider.com) The nameserver ns0.DOMAIN.IS is missing from the NS record set for DOMAIN.IS Test results for "NS1.DOMAIN.IS": The nameserver ns1.DOMAIN.IS is missing from the NS record set for DOMAIN.IS The nameserver ns0.DOMAIN.IS is missing from the NS record set for DOMAIN.IS This is really at the limits of my DNS knowledge I'm afraid. It feels like I'm close but maybe missing a vital part, linking the nameservers in Plesk or something?

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  • How do I uncompress vmlinuz to vmlinux?

    - by Lord Loh.
    I have already tried uncompress, gzip, and all other solutions that come up as google results and these have not worked for me. To get just the image search for the GZ signature - 1f 8b 08 00. > od -A d -t x1 vmlinuz | grep '1f 8b 08 00' 0024576 24 26 27 00 ae 21 16 00 1f 8b 08 00 7f 2f 6b 45 so the image begins at 24576+8 => 24584. Then just copy the image from the point and decompress it - > dd if=vmlinuz bs=1 skip=24584 | zcat > vmlinux 1450414+0 records in 1450414+0 records out 1450414 bytes (1.5 MB) copied, 6.78127 s, 214 kB/s Got these instructions verbatim from a forum online: http://www.codeguru.com/forum/showthread.php?t=415186 This process does not work for me and end up giving errors that states file not found 0024576 and all subsequent numbers. How do I proceed extracting vmlinux from vmlinuz? Thank you. EDITED: This is a reverse engineering question. I have no access to the distro to install any RPM or recompile. I start with nothing but vmlinuz.

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  • Cookieless Domain redirect in WHM/cPANEL

    - by Patrick Lanfranco
    I am currently trying to get my head around in understanding how to set-up a "cookieless" domain using WHM / Cpanel - unfortunately without any success at this moment. I have a Magento store and I would like to use "cookieless domains" for my media, skin (template) and js files. Magento has a nice feature to define URL for those folders. My current setup is as follows: www.mydomain.com <- main store media.mydomain.com <- subdomain to the media folder (mydomain.com/media/) skin.mydomain.com <- subdomain to the media folder (mydomain.com/skin/) js.mydomain.com <- subdomain to the media folder (mydomain.com/js/) I think it's poinless to have them used as "cookieliess domains" since my Magento installation uses .mydomain.com as cookie domain, so what I would like to achieve is to register a new additional domain and have it point via WHM / cPanel to those specific locations. I have tried to change the A and CNAME records although without any success as they were just simply redirecting from one page to another in the browser (newdomain.com - jump to old.com). What kind of records do I have to set to have this working properly? Some advice would be highly appreciated.

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  • SubDomain creation issue.Ubuntu 12.04 Apache 2.22 Webmin

    - by anarchos78
    I have a technical question concerning subdomains. My installation is UBUNTU 12.04 and WEBMIN for administration (using Apache web server). I am trying to create a subdomain to one IP (the domain is www.ithemis.gr and I want to create test.ithemis.gr and/or test1.ithemis.gr) with no success. I think I've tried the right way to set subdomains. The address does not resolving (I have already created DNS records via BIND). Do you have any suggestions? I am very new in server administration. Any help will be greatly appreciated! Apache configuration: In /etc/apache2/sites-available: Conf file:www.ithemis.gr.conf (main website) <VirtualHost 184.171.255.110:80> DocumentRoot /home/ithemis.gr ServerName www.ithemis.gr <Directory "/home/ithemis.gr"> allow from all #Options +Indexes Options +Includes -Indexes </Directory> </VirtualHost> Conf file:www.test.ithemis.gr.conf (subdomain website): <VirtualHost *:80> DocumentRoot /home/test.ithemis.gr ServerName test.ithemis.gr <Directory "/home/test.ithemis.gr"> allow from all Options +Indexes </Directory> </VirtualHost> My DNS records: Master Zone: ithemis.gr Name Type TTL Values ithemis.gr. NS Default ns1.themis.gr. ithemis.gr. A Default 184.171.255.110 ns1.ithemis.gr. A Default 184.171.255.110 ns2.ithemis.gr. A Default 184.171.255.110 mail.ithemis.gr. A Default 184.171.255.110 www.ithemis.gr. CNAME Default ithemis.gr. ithemis.gr. MX Default 5 mail.ithemis.gr. www.test.ithemis.gr. CNAME Default ithemis.gr. test.ithemis.gr. CNAME Default ithemis.gr.

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  • Dynamic DNS Updates with Wireless and Wired interfaces

    - by Phaedrus
    We have offices full of Windows & Mac users who obtain IP addresses from a Windows DHCP server, which in turn updates Dynamic DNS entries. We are noticing major inconsistencies with the entries, and have found that the problem is occurring more on Macs than on windows, and even more when users are frequently switching from wired to wireless adapter, which makes sense, as this sequence occurs: User enables wired adapter and registers Proper DNS User enables wireless adapter and registers 2nd proper DNS entry user switches off wireless manually and 2nd entry remains improperly until scavenge. Our help desk folks rely heavily (maybe more than they should) on the dynamic entries as part of their business process. For example, the user submits a help desk ticket, and the staff member expects to be able to remote desktop to their machine by hostname, which is hyperlinked in the helpdesk ticketing app. We have implemented multiple solutions & band-aids to different symptoms of the problems such as: Using DNS Reservations for Macintosh PCs Using DNS Scavenging to remove old records Switching from a Cisco DHCP server to the Windows DHCP Server But no matter what we do, it seems impossible to maintain perfect records. Has anyone encountered this problem before? What is industry best practice? Comments & Suggestions are much appreciated, /P

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  • SBS DC DNS entries going missing?

    - by Chris W
    I've been looking at a problem on a friends SBS (2003) server where the client PC's aren't able to connect to the server with a variety of errors reported. Checking the server itself the only indicator of an issue is an error 5782: Dynamic registration or deregistration of one or more DNS records failed with the following error: No DNS servers configured for the local system. Running a dcdiag reports that there are no DNS records registered for the DC so I fixed the problem by doing a netdiag /fix after which the dcdiag comes back clean and clients are ok again. It happened a few weeks ago as well and the same fix solved it. What are the possible causes of the DC DNS entries going missing? Is this a config option that needs tweaking or could it be solved by something simple like scheduling the SBS server to re-boot periodically? The only change they can think of that was made near to the time of the first instance of this problem occurring is that RRAS was started up to allow for a VPN connection from a home user. NB - The server is setup with a pair of NICs in a team so the server has a single virtual NIC providing both LAN/WAN connections to it. An external hardware firewall is in use rather than the windows firewall.

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  • Dns - wildcard vs. cname subdomains

    - by Matthew
    Alright I have to admit I'm confused with how DNS works. I've always just added things until they worked, and now it's time to learn how they work. So one confusing thing to me is that there's sort of two places I can have records. I have an account with rackspace cloud servers. And then there's the place I registered the domain. But both allow me to edit DNS records. Should I do everything at both places or is one better than the other or am I missing the point? Subdomains confuse me too. I'd like to be able to just have a wildcard subdomain (I've done this in the past.) I just don't like the idea of adding a cname record or A record every time I need a new subdomain. Then I read this and it says: The exact rules for when a wild card will match are specified in RFC 1034, but the rules are neither intuitive nor clearly specified. This has resulted in incompatible implementations and unexpected results when they are used.

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  • Can we do a DNSSEC 101? [closed]

    - by PAStheLoD
    Please share your opinions, FAQs, HOWTOs, best practices (or links to the one you think is the best) and your fears and thoughts about the whole migration (or should I just call it a new piece of tech?). Is DNSSEC just for DNS providers (name server operators)? What ought John Doe to do, who hosts johndoe.com at some random provider (GoDaddy, DreamHost and such)? Also, what if the provider's name server doesn't do automatic signing magic, can John do it manually? In a fire-and-forget way, without touching KSKs and ZSKs rollovers and updating and headaches?) Does it bring any change regarding CERT records? Do browsers support it? How come it became so complex? Why didn't they just merged it with SSL? DKIM is pretty straightforward, IANA/IETF could've opted for something like that. (Yes I know that creating a trust anchor would be still problematic, but browsers are already full of CA certs. So, they could've just let anyone get a cert for a domain for shiny green padlocks, or just generate one for a poor blue lock, put it into a TXT record, encrypt the other records and let the parent zone sign the whole for you with its cert.) Thanks! And for disclosure (it seemed like the customary thing to do around here), I've asked the same on the netsec subreddit.

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  • Apache Virtual Hosts behind Cisco Router

    - by Theo
    I'm setting up an Apache 2.2 Ubuntu web server for internal services that is also supposed to be accessed from outside our LAN. Our LAN has a single external IP that is the external IP of our RV042 Cisco router. We have set up several A records on our external DNS server that point to this IP. Our internal DNS server resolve the same records to the internal IP of our web server, so computers from inside the network can access them using the same address as if they were outside. We forwarded the router's external 80 port to our web server's 80 port. I have set up one Virtual Host for each domain name in our list, and my httpd.conf is something like this: ServerName web.domain.com NameVirtualHost *:80 <VirtualHost *:80> ServerName alfresco.domain.com <Proxy *> Order deny,allow Allow from all </Proxy> ProxyPass /alfresco http://localhost:8080/alfresco ProxyPassReverse /alfresco http://localhost:8080/alfresco ProxyPass /share http://localhost:8080/share ProxyPassReverse /share http://localhost:8080/share </VirtualHost> <VirtualHost *:80> ServerName crm.domain.com DocumentRoot /var/www/sugarcrm </VirtualHost> Now, this works if we are in our LAN. However, if we are outside of our LAN we reach our web server's default page saying: It Works! This is the default web page for this server. But we can't reach the virtual hosts, as if the domain name is not being preserved when the router forward the packets to the web server. Am I doing something wrong? How can I check what is going on? What should be the settings to make this work from outside?

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  • XAMPP server giving 404 error when requested by ipv4 connection

    - by boyb
    This is in reference to a previous question that I asked and was answered by womble. http://serverfault.com/a/406280/127729 So, now we have the real DNS records, we can do some diagnosis. dig for both A and AAAA on akosiboybastos.broker.freenet6.net gives a valid response, with an appropriate address. Good. dig for both A and AAAA on bastosforum.strangled.net gives the same responses (with a CNAME response thrown in). Also good. This means that the problem is not DNS-related, as those records are in order. wget -6 bastosforum.strangled.net/ gives a 200 OK response. wget -4 bastosforum.strangled.net/ gives a 404 Not Found response. This means that your webserver is misconfigured so that it's not serving the response you desire on IPv4. Given that the initial DNS problem asked in this question has been solved, I would recommend posting a new question with relevant webserver-related configuration, if you can't determine the configuration error yourself. I am using XAMPP(latest version) running phpbb3.0.10 via ipv6 tunnel from freenet6 and my domain is akosiboybastos.broker.freenet6.com, nothing fancy with the installation just out of the box install(with a few cosmetic mod). Both ipv4 and ipv6 traffic can connect using that url, but when I try to put a CNAME record on my test domain which is bastosforum.strangled.net pointing it to akosiboybastos.broker.freenet6.com only ipv6 can connect. As suggested by womble, this is a misconfigured webserver. To be honest I don't know where to start checking on the server as it is fully working if you use the domain given by freenet6 (akosiboybastos.broker.freenet6.com), any info on how to go about this server issue is welcome as i'm really a noob when it comes to computers. regards boyb

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  • mysqldump --where with = operator doesn't get all rows = - Help!

    - by JonathanLIVE
    I have a situation with a particular table that now thinks it contains 4 Petabytes of data. I know that sounds cool, but I assure you, it is only on a 60GB partition. This table has 9 fields in it. One of them is a domain_id field. It is the best field to identify the rows by, as there are only approximately 6300 of them. The only other field option to match has over 2million records, and thats just more difficult. I cannot do a straight mysqldump because it will attempt to output all 4PB of data and fill the drive long before it gets close to that, so I need to surgically remove the good stuff, destroy the db, and recreate it. I believe if I can do a dump for each domain_id record, then I will get most of the usable data out of it. This is what I am trying to use: mysqldump -u root --skip-opt -q --no-create-info --skip-add-drop-table --max_allowed_packet=1000000000 database table --where="domain_id=10" domains10.sql Using this I expect every row with the domain_id 10 to be exported. However, when I check the export, I am only getting 1 row, when however I look at the db, there are many many rows. It is as though the operator just finds one, then gives up. I have tried various operators. Using the < or I am able to get more of the data, but the export stops short at certain rows where the data has been compromised. With over 6000 to go through, I can't narrow down which rows are being affected in the export easily enough. So, what I need is an operator that will basically do what I thought = would do, simply give me an export of all records that match the specific field. Also note, the only way I got this DB even accessible is through an innodb force recovery 3. So I need to get this right, because after this is done, I have to drop the db in order to make mysql functional again. Looking forward to any helpful answers.

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  • Issues with returned mail sent to web-based email domains

    - by Beeder
    My company is having issues with returned mail that we send out to external domains. A few weeks ago we replaced a firewall and changed ISP providers and began subsequently having issues RECEIVING emails from external sources because we hadn't updated our new IPs in the DNS records. After making the necessary configuration changes and setting up SMTP forwarding over port 25 to our mail server, everything was working fine up until a few days ago when we started having mail sent out returned to us. We aren't having any trouble communicating internally (to recipients on our domain) but it seems we're having trouble with outbound messages to web-based email recipients. (@hotmail, @live, @yahoo, @gmail...etc) Currently we are running Server 2003 SP2 and exchange 2003. I'm very unfamiliar with configuring Exchange and could really use some help in narrowing down the possibilities. I did some research and am becoming suspicious of Sender ID being the culprit due to our recent IP address change and the likelihood that Sender ID is identifying us as a fake domain. Am I going in entirely the wrong direction? Any input or guidance would be infinitely appreciated. This is the message that is returned when an outbound message fails...this particular one was sent to my @live.com account for testing purposes... Your message did not reach some or all of the intended recipients. The following recipient(s) could not be reached: [email protected] on 5/17/2012 3:02 PM There was a SMTP communication problem with the recipient's email server. Please contact your system administrator. Unfortunately, messages from xx.x.xx.x weren't sent. Please contact your Internet service provider since part of their network is on our block list. I tried a reverse DNS lookup and found that we are set up as a Forward-confirmed reverse DNS. So do I just need to contact my ISP and have them correct their DNS records or is this something I can solve on our end??

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  • 5 year old server upgrade

    - by rizzo0917
    I am looking to upgrade a server for a web app. Currently the application is running very sluggish. We've made some adjustments to mysql (that's another issue in itself) and made some adjustments so that heaviest quires get run on a copy of the database on another server was have as a backup, however this will not last that much longer and we are looking to upgrade. Currently the servers CPUs are (4) Intel(R) XEON(TM) CPU 2.00GHz, with 1 gig of ram. The database is 442.5 MiB, with about 1,743,808 records. There are two parts of the program, the one, side a, inserts and updates most of the data. Side b, reads the data and does some minor updates. Currently our biggest day for side a are 800 users (of 40,000 users all year) imputing the system. And our Side b is currently unknown, however we have a total of 1000 clients. The system is most likely going to cap out at 5000 side b clients, with about a year 300,000 side a users. The current database is 5 years old, so we can most likely expect the database to grow pretty rapidly, possibly double each year (which we can most likely archive older records if it comes to that). So with that being said, should we get a server for each side of the app, side a being the master, side b being the slave, any updates made on side b are router to side a. So the question is should i get 2 of these or 1. 2 x Intel Nehalem Xeon E5520 2.26Ghz (8 Cores) 12GB DDRIII Memory 500GB SATAII HDD 100Mbps Port Speed And Naturally I would need to have a redundant backup so it could potentially be 4 of them.

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  • Mysql InnoDB and quickly applying large updates

    - by Tim
    Basically my problem is that I have a large table of about 17,000,000 products that I need to apply a bunch of updates to really quickly. The table has 30 columns with the id set as int(10) AUTO_INCREMENT. I have another table which all of the updates for this table are stored in, these updates have to be pre-calculated as they take a couple of days to calculate. This table is in the format of [ product_id int(10), update_value int(10) ]. The strategy I'm taking to issue these 17 million updates quickly is to load all of these updates into memory in a ruby script and group them in a hash of arrays so that each update_value is a key and each array is a list of sorted product_id's. { 150: => [1,2,3,4,5,6], 160: => [7,8,9,10] } Updates are then issued in the format of UPDATE product SET update_value = 150 WHERE product_id IN (1,2,3,4,5,6); UPDATE product SET update_value = 160 WHERE product_id IN (7,8,9,10); I'm pretty sure I'm doing this correctly in the sense that issuing the updates on sorted batches of product_id's should be the optimal way to do it with mysql / innodb. I'm hitting a weird issue though where when I was testing with updating ~13 million records, this only took around 45 minutes. Now I'm testing with more data, ~17 million records and the updates are taking closer to 120 minutes. I would have expected some sort of speed decrease here but not to the degree that I'm seeing. Any advice on how I can speed this up or what could be slowing me down with this larger record set? As far as server specs go they're pretty good, heaps of memory / cpu, the whole DB should fit into memory with plenty of room to grow.

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  • Easily use google maps, openstreet maps etc offline.

    - by samkea
    I did it and i am going to explain step by step. The explanatination may appear long but its simple if you follow. Note: All the softwares i have used are the latest and i have packaged them and provided them in the link below. I use Nokia N96 1) RootSign smartComGPS and install it on your phone(i havent provided the signer so that u wuld do some little work. i used Secman' rootsign). 2) Install Universal Maps Downloader, SmartCom OGF2 converter and OziExplorer 3.95.4s on my PC. a) UMD is used to download map tiles from any map source like googlemaps,opensourcemaps etc... and also combine the tiles into an image file like png,jpg,bmp etc... b) SmartCom OGF2 converter is used to convert the image file into a format usable on your mobile phone. c) OziExplorer will help you to calibrate the usable map file so that it can be used with GPS on your mobile phone without the use of internet. 3) Go to google maps or where u pick your maps and pan to the area of your interest. Zoom the map to at least 15 or 16 zoom level where you can see your area clearly and the streets. 4) copy this script in a notepad file and save it on your desktop: javascript:void(prompt('',gApplication.getMap().ge tCenter())); 5) Open the universal maps downloader. You will notice that you are required to add the: left longitude, right longitude,top latitude, bottom latitude. 6) On your map in google maps, doubleclick on the your prefered to most middle point. you will notice that the map will center in that area. 7) copy the script and paste it in the address bar then press enter. You will notice that a dialog with your (top latitude) and longitude respectively pops up. 8) copy the top latitude ONLY and paste it in the corresponding textbox in the UMD. 9) repeat steps 6-7 for the botton latitude. 10)repeat steps 6-7 for left longitude and right longitude too, but u have to copy the longitudes here. (***BTW record these points in the text file as they may be needed later in calibration) 11) Give the zoom level to the same zoom level that you prefered in google maps. 12) Dont forget to choose a path to save your files and under options set the proxy connection settings in UMD if you are using so. 13) Click on start and bingo! there you have your image tiles and a file with an extension .umd will be saved in the same folder. 14) On the UMD, go to tools, click on MapViewer and choose the .umd file. you will now see your map in one piece....and you will smile! 15) Still go to tools and click on map combiner. A dialog will popup for you to choose the .umd file and to enter the IMAGE file name. u can use another extension for the image file like png, jpg etc...i usually use png. 16) Combine.....bingo! there u go! u have an IMAGE file for your map. *I SUGGEST THAT CREATE A .BMP FILE and A .PNG file* 17) Close UMD and open SmartCom OGF2 converter. 18) Choose your .png image and create an ogf2 file. 19) Connect your phone to your PC in Mass Memory mode and transfer the file to the smartComGPS\Maps folder. 20) Now disconnect your phone and load smartComGPS. it will load the map and propt you to add a calibration point. Go ahead and add one calibration point with dummy coordinates. You will notice that it will add another file with extension .map in the smartComGPS\Maps folder. 21) Connect yiur ohone and copy that file and paste it in your working folder on your PC. Delete that .map file from the phone too because you are going to edit it from your PC and put it back. 22) Now Open the OziExplorer, go to file-->Load and Calibrate Map Image. 23) Choose the .bmp image and bingo! it will load with your map in the same zoom level. 24) Now you are going to calibrate. Use the MapView window and take the small box locater to all the 4 cornners of the map. You will notice that the map in the back ground moves to that area too. 25)On the right side, select the Point1 tab. Now you are in calibration mode. Now move the red box in mapview in the left upper corner to calibrate point1. 26) out of mapview go to the the left upper corner of the background map and choose poit (0,0) and your 1st calibration point. You will notice that these X,Y cordinated will be reflected in the Point1 image cordinates. 27) now go back to the text file where you saved your coordibates and enter the top latitude and the left longitude in the corresponding places. 28) Repeat steps 25-27 for point2,point3,point4 and click on save. Thats it, you have calibrated your image and you are about to finish. 29) Go to save and a dilaog which prompts you to save a .map file will poop up. Do save the map file in your working folder. 30) Right click that .map file and edit the filename in the .map file to remove the pc's directory structure. Eg. Change C\OziExplorer\data\Kampala.bmp to Kampala.ogf2. 31) Save the .map file in the smartComGPS\Maps folder on your phone. 32) now open smartComGPS on your phone and bingo! there is your map with GPS capability and in the same zoom level. 33) In smartComGPS options, choose connect and simulate. By now you should be smiling. Whoa! Hope i was of help. i case you get a problem, please inform me Below is the link to the software. regards. http://rapidshare.com/files/230296037/Utilities_Used.rar.html Ok, the Rapidshare files i posted are gone, so you will have to download as described in the solution. If you need more help, go here: http://www.dotsis.com/mobile_phone/sitemap/t-160491.html Some months later, someone else gave almost the same kind of solution here. http://www.dotsis.com/mobile_phone/sitemap/t-180123.html Note: the solutions were mean't to help view maps on Symbian phones, but i think now they ca even do for Windows Phones, iphones and others so read, extract what you want and use it. Hope it helps. Sam Kea

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  • A Guided Tour of Complexity

    - by JoshReuben
    I just re-read Complexity – A Guided Tour by Melanie Mitchell , protégé of Douglas Hofstadter ( author of “Gödel, Escher, Bach”) http://www.amazon.com/Complexity-Guided-Tour-Melanie-Mitchell/dp/0199798109/ref=sr_1_1?ie=UTF8&qid=1339744329&sr=8-1 here are some notes and links:   Evolved from Cybernetics, General Systems Theory, Synergetics some interesting transdisciplinary fields to investigate: Chaos Theory - http://en.wikipedia.org/wiki/Chaos_theory – small differences in initial conditions (such as those due to rounding errors in numerical computation) yield widely diverging outcomes for chaotic systems, rendering long-term prediction impossible. System Dynamics / Cybernetics - http://en.wikipedia.org/wiki/System_Dynamics – study of how feedback changes system behavior Network Theory - http://en.wikipedia.org/wiki/Network_theory – leverage Graph Theory to analyze symmetric  / asymmetric relations between discrete objects Algebraic Topology - http://en.wikipedia.org/wiki/Algebraic_topology – leverage abstract algebra to analyze topological spaces There are limits to deterministic systems & to computation. Chaos Theory definitely applies to training an ANN (artificial neural network) – different weights will emerge depending upon the random selection of the training set. In recursive Non-Linear systems http://en.wikipedia.org/wiki/Nonlinear_system – output is not directly inferable from input. E.g. a Logistic map: Xt+1 = R Xt(1-Xt) Different types of bifurcations, attractor states and oscillations may occur – e.g. a Lorenz Attractor http://en.wikipedia.org/wiki/Lorenz_system Feigenbaum Constants http://en.wikipedia.org/wiki/Feigenbaum_constants express ratios in a bifurcation diagram for a non-linear map – the convergent limit of R (the rate of period-doubling bifurcations) is 4.6692016 Maxwell’s Demon - http://en.wikipedia.org/wiki/Maxwell%27s_demon - the Second Law of Thermodynamics has only a statistical certainty – the universe (and thus information) tends towards entropy. While any computation can theoretically be done without expending energy, with finite memory, the act of erasing memory is permanent and increases entropy. Life & thought is a counter-example to the universe’s tendency towards entropy. Leo Szilard and later Claude Shannon came up with the Information Theory of Entropy - http://en.wikipedia.org/wiki/Entropy_(information_theory) whereby Shannon entropy quantifies the expected value of a message’s information in bits in order to determine channel capacity and leverage Coding Theory (compression analysis). Ludwig Boltzmann came up with Statistical Mechanics - http://en.wikipedia.org/wiki/Statistical_mechanics – whereby our Newtonian perception of continuous reality is a probabilistic and statistical aggregate of many discrete quantum microstates. This is relevant for Quantum Information Theory http://en.wikipedia.org/wiki/Quantum_information and the Physics of Information - http://en.wikipedia.org/wiki/Physical_information. Hilbert’s Problems http://en.wikipedia.org/wiki/Hilbert's_problems pondered whether mathematics is complete, consistent, and decidable (the Decision Problem – http://en.wikipedia.org/wiki/Entscheidungsproblem – is there always an algorithm that can determine whether a statement is true).  Godel’s Incompleteness Theorems http://en.wikipedia.org/wiki/G%C3%B6del's_incompleteness_theorems  proved that mathematics cannot be both complete and consistent (e.g. “This statement is not provable”). Turing through the use of Turing Machines (http://en.wikipedia.org/wiki/Turing_machine symbol processors that can prove mathematical statements) and Universal Turing Machines (http://en.wikipedia.org/wiki/Universal_Turing_machine Turing Machines that can emulate other any Turing Machine via accepting programs as well as data as input symbols) that computation is limited by demonstrating the Halting Problem http://en.wikipedia.org/wiki/Halting_problem (is is not possible to know when a program will complete – you cannot build an infinite loop detector). You may be used to thinking of 1 / 2 / 3 dimensional systems, but Fractal http://en.wikipedia.org/wiki/Fractal systems are defined by self-similarity & have non-integer Hausdorff Dimensions !!!  http://en.wikipedia.org/wiki/List_of_fractals_by_Hausdorff_dimension – the fractal dimension quantifies the number of copies of a self similar object at each level of detail – eg Koch Snowflake - http://en.wikipedia.org/wiki/Koch_snowflake Definitions of complexity: size, Shannon entropy, Algorithmic Information Content (http://en.wikipedia.org/wiki/Algorithmic_information_theory - size of shortest program that can generate a description of an object) Logical depth (amount of info processed), thermodynamic depth (resources required). Complexity is statistical and fractal. John Von Neumann’s other machine was the Self-Reproducing Automaton http://en.wikipedia.org/wiki/Self-replicating_machine  . Cellular Automata http://en.wikipedia.org/wiki/Cellular_automaton are alternative form of Universal Turing machine to traditional Von Neumann machines where grid cells are locally synchronized with their neighbors according to a rule. Conway’s Game of Life http://en.wikipedia.org/wiki/Conway's_Game_of_Life demonstrates various emergent constructs such as “Glider Guns” and “Spaceships”. Cellular Automatons are not practical because logical ops require a large number of cells – wasteful & inefficient. There are no compilers or general program languages available for Cellular Automatons (as far as I am aware). Random Boolean Networks http://en.wikipedia.org/wiki/Boolean_network are extensions of cellular automata where nodes are connected at random (not to spatial neighbors) and each node has its own rule –> they demonstrate the emergence of complex  & self organized behavior. Stephen Wolfram’s (creator of Mathematica, so give him the benefit of the doubt) New Kind of Science http://en.wikipedia.org/wiki/A_New_Kind_of_Science proposes the universe may be a discrete Finite State Automata http://en.wikipedia.org/wiki/Finite-state_machine whereby reality emerges from simple rules. I am 2/3 through this book. It is feasible that the universe is quantum discrete at the plank scale and that it computes itself – Digital Physics: http://en.wikipedia.org/wiki/Digital_physics – a simulated reality? Anyway, all behavior is supposedly derived from simple algorithmic rules & falls into 4 patterns: uniform , nested / cyclical, random (Rule 30 http://en.wikipedia.org/wiki/Rule_30) & mixed (Rule 110 - http://en.wikipedia.org/wiki/Rule_110 localized structures – it is this that is interesting). interaction between colliding propagating signal inputs is then information processing. Wolfram proposes the Principle of Computational Equivalence - http://mathworld.wolfram.com/PrincipleofComputationalEquivalence.html - all processes that are not obviously simple can be viewed as computations of equivalent sophistication. Meaning in information may emerge from analogy & conceptual slippages – see the CopyCat program: http://cognitrn.psych.indiana.edu/rgoldsto/courses/concepts/copycat.pdf Scale Free Networks http://en.wikipedia.org/wiki/Scale-free_network have a distribution governed by a Power Law (http://en.wikipedia.org/wiki/Power_law - much more common than Normal Distribution). They are characterized by hubs (resilience to random deletion of nodes), heterogeneity of degree values, self similarity, & small world structure. They grow via preferential attachment http://en.wikipedia.org/wiki/Preferential_attachment – tipping points triggered by positive feedback loops. 2 theories of cascading system failures in complex systems are Self-Organized Criticality http://en.wikipedia.org/wiki/Self-organized_criticality and Highly Optimized Tolerance http://en.wikipedia.org/wiki/Highly_optimized_tolerance. Computational Mechanics http://en.wikipedia.org/wiki/Computational_mechanics – use of computational methods to study phenomena governed by the principles of mechanics. This book is a great intuition pump, but does not cover the more mathematical subject of Computational Complexity Theory – http://en.wikipedia.org/wiki/Computational_complexity_theory I am currently reading this book on this subject: http://www.amazon.com/Computational-Complexity-Christos-H-Papadimitriou/dp/0201530821/ref=pd_sim_b_1   stay tuned for that review!

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  • Sync Your Pidgin Profile Across Multiple PCs with Dropbox

    - by Matthew Guay
    Pidgin is definitely our favorite universal chat client, but adding all of your chat accounts to multiple computers can be frustrating.  Here’s how you can easily transfer your Pidgin settings to other computers and keep them in sync using Dropbox. Getting Started Make sure you have both Pidgin and Dropbox installed on any computers you want to sync.  To sync Pidgin, you need to: Move your Pidgin profile folder on your first computer to Dropbox Create a symbolic link from the new folder in Dropbox to your old profile location Delete the default pidgin profile on your other computer, and create a symbolic link from your Dropbox Pidgin profile to the default Pidgin profile location This sounds difficult, but it’s actually easy if you follow these steps.  Here we already had all of our accounts setup in Pidgin in Windows 7, and then synced this profile with an Ubuntu and a XP computer with fresh Pidgin installs.  Our instructions for each OS are based on this, but just swap the sync order if your main Pidgin install is in XP or Ubuntu. Please Note:  Please make sure Pidgin isn’t running on your computer while you are making the changes! Sync Your Pidgin Profile from Windows 7 Here is Pidgin with our accounts already setup.  Our Pidgin profile has a Gtalk, MSN Messenger, and Facebook Chat account, and lots of log files. Let’s move this profile to Dropbox to keep it synced.  Exit Pidgin, and then enter %appdata% in the address bar in Explorer or press Win+R and enter %appdata%.  Select the .purple folder, which is your Pidgin profiles and settings folder, and press Ctrl+X to cut it. Browse to your Dropbox folder, and press Ctrl+V to paste the .purple folder there. Now we need to create the symbolic link.  Enter  “command” in your Start menu search, right-click on the Command Prompt shortcut, and select “Run as administrator”. We can now use the mklink command to create a symbolic link to the .purple folder.  In Command Prompt, enter the following and substitute username for your own username. mklink /D “C:\Users\username\Documents\My Dropbox\.purple” “C:\Users\username\AppData\Roaming\.purple” And that’s it!  You can open Pidgin now to make sure it still works as before, with your files being synced with Dropbox. Please Note:  These instructions work the same for Windows Vista.  Also, if you are syncing settings from another computer to Windows 7, then delete the .purple folder instead of cutting and pasting it, and reverse the order of the file paths when creating the symbolic link. Add your Pidgin Profile to Ubuntu Our Ubuntu computer had a clean install of Pidgin, so we didn’t need any of the information in its settings.  If you’ve run Pidgin, even without creating an account, you will need to first remove its settings folder.  Open your home folder, and click View, and then “Show Hidden Files” to see your settings folders. Select the .purple folder, and delete it. Now, to create the symbolic link, open Terminal and enter the following, substituting username for your username: ln –s /home/username/Dropbox/.purple /home/username/ Open Pidgin, and you will see all of your accounts that were on your other computer.  No usernames or passwords needed; everything is setup and ready to go.  Even your status is synced; we had our status set to Away in Windows 7, and it automatically came up the same in Ubuntu. Please Note: If your primary Pidgin account is in Ubuntu, then cut your .purple folder and paste it into your Dropbox folder instead.  Then, when creating the symbolic link, reverse the order of the folder paths. Add your Pidgin Profile to Windows XP In XP we also had a clean install of Pidgin.  If you’ve run Pidgin, even without creating an account, you will need to first remove its settings folder.  Click Start, the Run, and enter %appdata%. Delete your .purple folder. XP does not include a way to create a symbolic link, so we will use the free Junction tool from Sysinternals.  Download Junction (link below) and unzip the folder. Open Command Prompt (click Start, select All Programs, then Accessories, and select Command Prompt), and enter cd followed by the path of the folder where you saved Junction.   Now, to create the symbolic link, enter the following in Command Prompt, substituting username with your username. junction –d “C:\Documents and Settings\username\Application Data\.purple” “C:\Documents and Settings\username\My Documents\My Dropbox\.purple” Open Pidgin, and you will see all of your settings just as they were on your other computer.  Everything’s ready to go.   Please Note: If your primary Pidgin account is in Windows XP, then cut your .purple folder and paste it into your Dropbox folder instead.  Then, when creating the symbolic link, reverse the order of the folder paths. Conclusion This is a great way to keep all of your chat and IM accounts available from all of your computers.  You can easily access logs from chats you had on your desktop from your laptop, or if you add a chat account on your work computer you can use it seamlessly from your home computer that evening.  Now Pidgin is the universal chat client that is always ready whenever and wherever you need it! Links Downlaod Pidgin Download and signup for Dropbox Download Junction for XP Similar Articles Productive Geek Tips Add "My Dropbox" to Your Windows 7 Start MenuUse Multiple Firefox Profiles at the Same TimeEasily Add Facebook Chat to PidginPut Your Pidgin Buddy List into the Windows Vista SidebarBackup and Restore Firefox Profiles Easily TouchFreeze Alternative in AutoHotkey The Icy Undertow Desktop Windows Home Server – Backup to LAN The Clear & Clean Desktop Use This Bookmarklet to Easily Get Albums Use AutoHotkey to Assign a Hotkey to a Specific Window Latest Software Reviews Tinyhacker Random Tips DVDFab 6 Revo Uninstaller Pro Registry Mechanic 9 for Windows PC Tools Internet Security Suite 2010 Download Free iPad Wallpapers at iPad Decor Get Your Delicious Bookmarks In Firefox’s Awesome Bar Manage Photos Across Different Social Sites With Dropico Test Drive Windows 7 Online Download Wallpapers From National Geographic Site Spyware Blaster v4.3

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  • Introducción a ENUM (E.164 Number Mapping)

    - by raul.goycoolea
    E.164 Number Mapping (ENUM o Enum) se diseñó para resolver la cuestión de como se pueden encontrar servicios de internet mediante un número telefónico, es decir cómo se pueden usar los los teléfonos, que solamente tienen 12 teclas, para acceder a servicios de Internet. La parte más básica de ENUM es por tanto la convergencia de las redes del STDP y la IP; ENUM hace que pueda haber una correspondencia entre un número telefónico y un identificador de Internet. En síntesis, Enum es un conjunto de protocolos para convertir números E.164 en URIs, y viceversa, de modo que el sistema de numeración E.164 tenga una función de correspondencia con las direcciones URI en Internet. Esta función es necesaria porque un número telefónico no tiene sentido en el mundo IP, ni una dirección IP tiene sentido en las redes telefónicas. Así, mediante esta técnica, las comunicaciones cuyo destino se marque con un número E.164, puedan terminar en el identificador correcto (número E.164 si termina en el STDP, o URI si termina en redes IP). La solución técnica de mirar en una base de datos cual es el identificador de destino tiene consecuencias muy interesantes, como que la llamada se pueda terminar donde desee el abonado llamado. Esta es una de las características que ofrece ENUM : el destino concreto, el terminal o terminales de terminación, no lo decide quien inicia la llamada o envía el mensaje sino la persona que es llamada o recibe el mensaje, que ha escrito sus preferencias en una base de datos. En otras palabras, el destinatario de la llamada decide cómo quiere ser contactado, tanto si lo que se le comunica es un email, o un sms, o telefax, o una llamada de voz. Cuando alguien quiera llamarle a usted, lo que tiene que hacer el llamante es seleccionar su nombre (el del llamado) en la libreta de direcciones del terminal o marcar su número ENUM. Una aplicación informática obtendrá de una base de datos los datos de contacto y disponibilidad que usted decidió. Y el mensaje le será remitido tal como usted especificó en dicha base de datos. Esto es algo nuevo que permite que usted, como persona llamada, defina sus preferencias de terminación para cualquier tipo de contenido. Por ejemplo, usted puede querer que todos los emails le sean enviados como sms o que los mensajes de voz se le remitan como emails; las comunicaciones ya no dependen de donde esté usted o deque tipo de terminal utiliza (teléfono, pda, internet). Además, con ENUM usted puede gestionar la portabilidad de sus números fijos y móviles. ENUM emplea una técnica de búsqueda indirecta en una base de datos que tiene los registros NAPTR ("Naming Authority Pointer Resource Records" tal como lo define el RFC 2915), y que utiliza el número telefónico Enum como clave de búsqueda, para obtener qué URIs corresponden a cada número telefónico. La base de datos que almacena estos registros es del tipo DNS.Si bien en uno de sus diversos usos sirve para facilitar las llamadas de usuarios de VoIP entre redes tradicionales del STDP y redes IP, debe tenerse en cuenta que ENUM no es una función de VoIP sino que es un mecanismo de conversión entre números/identificadores. Por tanto no debe ser confundido con el uso normal de enrutar las llamadas de VoIP mediante los protocolos SIP y H.323. ENUM puede ser muy útil para aquellas organizaciones que quieran tener normalizada la manera en que las aplicaciones acceden a los datos de comunicación de cada usuario. FundamentosPara que la convergencia entre el Sistema Telefónico Disponible al Público (STDP) y la Telefonía por Internet o Voz sobre IP (VoIP) y que el desarrollo de nuevos servicios multimedia tengan menos obstáculos, es fundamental que los usuarios puedan realizar sus llamadas tal como están acostumbrados a hacerlo, marcando números. Para eso, es preciso que haya un sistema universal de correspondencia de número a direcciones IP (y viceversa) y que las diferentes redes se puedan interconectar. Hay varias fórmulas que permiten que un número telefónico sirva para establecer comunicación con múltiples servicios. Una de estas fórmulas es el Electronic Number Mapping System ENUM, normalizado por el grupo de tareas especiales de ingeniería en Internet (IETF, Internet engineering task force), del que trata este artículo, que emplea la numeración E.164, los protocolos y la infraestructura telefónica para acceder indirectamente a diferentes servicios. Por tanto, se accede a un servicio mediante un identificador numérico universal: un número telefónico tradicional. ENUM permite comunicar las direcciones del mundo IP con las del mundo telefónico, y viceversa, sin problemas. Antes de entrar en mayores profundidades, conviene dar una breve pincelada para aclarar cómo se organiza la correspondencia entre números o URI. Para ello imaginemos una llamada que se inicia desde el servicio telefónico tradicional con destino a un número Enum. En ENUM Público, el abonado o usuario Enum a quien va destinada lallamada, habrá decidido incluir en la base de datos Enum uno o varios URI o números E.164, que forman una lista con sus preferencias para terminar la llamada. Y el sistema como se explica más adelante, elegirá cual es el número o URI adecuado para dicha terminación. Por tanto como resultado de la consulta a la base dedatos Enum siempre se da una relación unívoca entre el número Enum marcado y el de terminación, conforme a los deseos de la persona llamada.Variedades de ENUMUna posible fuente de confusión cuando se trata sobre ENUM es la variedad de soluciones o sistemas que emplean este calificativo. Lo habitual es que cuando se haga una referencia a ENUM se trate de uno de los siguientes casos: ENUM Público: Es la visión original de ENUM, como base de datos pública, parecida a un directorio, donde el abonado "opta" a ser incluido en la base de datos, que está gestionada en el dominio e164.arpa, delegando a cada país la gestión de la base de datos y la numeración. También se conoce como ENUM de usuario. Carrier ENUM, o ENUM Infraestructura, o de Operador: Cuando grupos de operadores proveedores de servicios de comunicaciones electrónicas acuerdan compartir la información de los abonados por medio de ENUM mediante acuerdos privados. En este caso son los operadores quienes controlan la información del abonado en vez de hacerlo (optar) los propios abonados. Carrier ENUM o ENUM de Operador también se conoce como Infrastructure ENUM o ENUM Infraestructura, y está siendo normalizado por IETF para la interconexión de VoIP (mediante acuerdos de peering). Como se explicará en la correspondiente sección, también se puede utilizar para la portabilidad o conservación de número. ENUM Privado: Un operador de telefonía o de VoIP, o un ISP, o un gran usuario, puede utilizar las técnicas de ENUM en sus redes y en las de sus clientes sin emplear DNS públicos, con DNS privados o internos. Resulta fácil imaginar como puede utilizarse esta técnica para que compañías multinacionales, o bancos, o agencias de viajes, tengan planes de numeración muy coherentes y eficaces. Cómo funciona ENUMPara conocer cómo funciona Enum, le remitimos a la página correspondiente a ENUM Público, puesto que esa variedad de Enum es la típica, la que dió lugar a todos los procedimientos y normas de IETF .Más detalles sobre: @page { margin: 0.79in } P { margin-bottom: 0.08in } H4 { margin-bottom: 0.08in } H4.ctl { font-family: "Lohit Hindi" } A:link { so-language: zxx } -- ENUM Público. En esta página se explica con cierto detalle como funciona Enum Carrier ENUM o ENUM de Operador ENUM Privado Normas técnicas: RFC 2915: NAPTR RR. The Naming Authority Pointer (NAPTR) DNS Resource Record RFC 3761: ENUM Protocol. The E.164 to Uniform Resource Identifiers (URI) Dynamic Delegation Discovery System (DDDS) Application (ENUM). (obsoletes RFC 2916). RFC 3762: Usage of H323 addresses in ENUM Protocol RFC 3764: Usage of SIP addresses in ENUM Protocol RFC 3824: Using E.164 numbers with SIP RFC 4769: IANA Registration for an Enumservice Containing Public Switched Telephone Network (PSTN) Signaling Information RFC 3026: Berlin Liaison Statement RFC 3953: Telephone Number Mapping (ENUM) Service Registration for Presence Services RFC 2870: Root Name Server Operational Requirements RFC 3482: Number Portability in the Global Switched Telephone Network (GSTN): An Overview RFC 2168: Resolution of Uniform Resource Identifiers using the Domain Name System Organizaciones relacionadas con ENUM RIPE - Adimistrador del nivel 0 de ENUM e164.arpa. ITU-T TSB - Unión Internacional de Telecomunicaciones ETSI - European Telecommunications Standards Institute VisionNG - Administrador del rango ENUM 878-10 IETF ENUM Chapter

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  • Beginning Java (Working with Arrays; Class Assignment)

    - by Jason
    I am to the point where I feel as if I correctly wrote the code for this homework assignment. We were given a skeleton and 2 classes that we had to import (FileIOHelper and Student). /* * Created: *** put the date here *** * * Author: *** put your name here *** * * The program will read information about students and their * scores from a file, and output the name of each student with * all his/her scores and the total score, plus the average score * of the class, and the name and total score of the students with * the highest and lowest total score. */ // import java.util.Scanner; import java.io.*; // C:\Users\Adam\info.txt public class Lab6 { public static void main(String[] args) throws IOException { // Fill in the body according to the following comments Scanner key boardFile = new Scanner(System.in); // Input file name String filename = getFileName(keyboardFile); //Open the file // Input number of students int numStudents = FileIOHelper.getNumberOfStudents(filename); Student students[] = new Student[numStudents]; // Input all student records and create Student array and // integer array for total scores int totalScore[] = new int[students.length]; for (int i = 0; i < students.length; i++){ for(int j = 1; j < 4; j++){ totalScore[i] = totalScore[i] + students[i].getScore(j); } } // Compute total scores and find students with lowest and // highest total score int maxScore = 0; int minScore = 0; for(int i = 0; i < students.length; i++){ if(totalScore[i] >= totalScore[maxScore]){ maxScore = i; } else if(totalScore[i] <= totalScore[minScore]){ minScore = i; } } // Compute average total score int allScores = 0; int average = 0; for (int i = 0; i < totalScore.length; i++){ allScores = allScores + totalScore[i]; } average = allScores / totalScore.length; // Output results outputResults(students, totalScore, maxScore, minScore, average); } // Given a Scanner in, this method prompts the user to enter // a file name, inputs it, and returns it. private static String getFileName(Scanner in) { // Fill in the body System.out.print("Enter the name of a file: "); String filename = in.next(); return filename; // Do not declare the Scanner variable in this method. // You must use the value this method receives in the // argument (in). } // Given the number of students records n to input, this // method creates an array of Student of the appropriate size, // reads n student records using the FileIOHelper, and stores // them in the array, and finally returns the Student array. private static Student[] getStudents(int n) { Student[] myStudents = new Student[n]; for(int i = 0; i <= n; i++){ myStudents[i] = FileIOHelper.getNextStudent(); } return myStudents; } // Given an array of Student records, an array with the total scores, // the indices in the arrays of the students with the highest and // lowest total scores, and the average total score for the class, // this method outputs a table of all the students appropriately // formatted, plus the total number of students, the average score // of the class, and the name and total score of the students with // the highest and lowest total score. private static void outputResults( Student[] students, int[] totalScores, int maxIndex, int minIndex, int average ) { // Fill in the body System.out.println("\nName \t\tScore1 \tScore2 \tScore3 \tTotal"); System.out.println("--------------------------------------------------------"); for(int i = 0; i < students.length; i++){ outputStudent(students[i], totalScores[i], average); System.out.println(); } System.out.println("--------------------------------------------------------"); outputNumberOfStudents(students.length); outputAverage(average); outputMaxStudent(students[maxIndex], totalScores[maxIndex]); outputMinStudent(students[minIndex], totalScores[minIndex]); System.out.println("--------------------------------------------------------"); } // Given a Student record, the total score for the student, // and the average total score for all the students, this method // outputs one line in the result table appropriately formatted. private static void outputStudent(Student s, int total, int avg) { System.out.print(s.getName() + "\t"); for(int i = 1; i < 4; i++){ System.out.print(s.getScore(i) + "\t"); } System.out.print(total + "\t"); if(total < avg){ System.out.print("-"); }else if(total > avg){ System.out.print("+"); }else{ System.out.print("="); } } // Given the number of students, this method outputs a message // stating what the total number of students in the class is. private static void outputNumberOfStudents(int n) { System.out.println("The total number of students in this class is: \t" + n); } // Given the average total score of all students, this method // outputs a message stating what the average total score of // the class is. private static void outputAverage(int average) { System.out.println("The average total score of the class is: \t" + average); } // Given the Student with highest total score and the student's // total score, this method outputs a message stating the name // of the student and the highest score. private static void outputMaxStudent( Student student, int score ) { System.out.println(student.getName() + " got the maximum total score of: \t" + score); } // Given the Student with lowest total score and the student's // total score, this method outputs a message stating the name // of the student and the lowest score. private static void outputMinStudent( Student student, int score ) { System.out.println(student.getName() + " got the minimum total score of: \t" + score); } } But now I get an error at the line totalScore[i] = totalScore[i] + students[i].getScore(j); Exception in thread "main" java.lang.NullPointerException at Lab6.main(Lab6.java:42)

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  • Python regex to parse text file, get the items in list and count the list

    - by Nemo
    I have a text file which contains some data. I m particularly interested in finding the count of the number of items in v_dims v_dims pattern in my text file looks like this : v_dims={ "Sales", "Product Family", "Sales Organization", "Region", "Sales Area", "Sales office", "Sales Division", "Sales Person", "Sales Channel", "Sales Order Type", "Sales Number", "Sales Person", "Sales Quantity", "Sales Amount" } So I m thinking of getting all the elements in v_dims and dumping them out in a Python list. Then compute the len(mylist) to get the count of the items. The challenge is in getting all the elements of v_dims from my text file and putting them in an empty list. I m particularly interested in items in v_dims in my text file. The text file has data in the form of v_dims pattern i showed in my original post. Some data has nested patterns of v_dims. Thanks. Here's what I have tried and failed. Any help is appreciated. TIA. import re fname = "C:\Users\XXXX\Test.mrk" with open(fname, "r") as fo: content_as_string = fo.read() match = re.findall(r'v_dims={\"(.+?)\"}',content_as_string) Though I have a big text file, Here's a snippet of what's the structure of my text file version "1"; // Computer generated object language file object 'MRKR' "Main" { Data_Type=2, HeaderBlock={ Version_String="6.3 (25)" }, Printer_Info={ Orientation=0, Page_Width=8.50000000, Page_Height=11.00000000, Page_Header="", Page_Footer="", Margin_type=0, Top_Margin=0.50000000, Left_Margin=0.50000000, Bottom_Margin=0.50000000, Right_Margin=0.50000000 }, Marker_Options={ Close_All="TRUE", Hide_Console="FALSE", Console_Left="FALSE", Console_Width=217, Main_Style="Maximized", MDI_Rect={ 0, 0, 892, 1063 } }, Dives={ { Dive="A", Windows={ { View_Index=0, Window_Info={ Window_Rect={ 0, -288, 400, 1008 }, Window_Style="Maximized Front", Window_Name="Theater [Previous Qtr Diveplan-Dive A]" }, Dependent_bool="FALSE", Colset={ Dive_Type="Normal", Dimension_Name="Theater", Action_List={ Actions={ { Action_Type="Select", select_type=5 }, { Action_Type="Select", select_type=0, Key_Names={ "Theater" }, Key_Indexes={ { "AMERICAS" } } }, { Action_Type="Focus", Focus_Rows="True" }, { Action_Type="Dimensions", v_dims={ "Theater", "Product Family", "Division", "Region", "Install at Country Name", "Connect Home Type", "Connect In Type", "SymmConnect Enabled", "Connect Home Refusal Reason", "Sales Order Channel Type", "Maintained By Group", "PS Flag", "Avalanche Flag", "Product Item Family" }, Xtab_Bool="False", Xtab_Flip="False" }, { Action_Type="Select", select_type=5 }, { Action_Type="Select", select_type=0, Key_Names={ "Theater", "Product Family", "Division", "Region", "Install at Country Name", "Connect Home Type", "Connect In Type", "SymmConnect Enabled", "Connect Home Refusal Reason", "Sales Order Channel Type", "Maintained By Group", "PS Flag", "Avalanche Flag" }, Key_Indexes={ { "AMERICAS", "ATMOS", "Latin America CS Division", "37000 CS Region", "Mexico", "", "", "", "", "DIRECT", "EMC", "N", "0" } } } } }, Num_Palette_cols=0, Num_Palette_rows=0 }, Format={ Window_Type="Tabular", Tabular={ Num_row_labels=8 } } } } } }, Widget_Set={ Widget_Layout="Vertical", Go_Button=1, Picklist_Width=0, Sort_Subset_Dimensions="TRUE", Order={ } }, Views={ { Data_Type=1, dbname="Previous Qtr Diveplan", diveline_dbname="Current Qtr Diveplan", logical_name="Current Qtr Diveplan", cols={ { name="Total TSS installs", column_type="Calc[Total TSS installs]", output_type="Number", format_string="." }, { name="TSS Valid Connectivity Records", column_type="Calc[TSS Valid Connectivity Records]", output_type="Number", format_string="." }, { name="% TSS Connectivity Record", column_type="Calc[% TSS Connectivity Record]", output_type="Number" }, { name="TSS Not Applicable", column_type="Calc[TSS Not Applicable]", output_type="Number", format_string="." }, { name="TSS Customer Refusals", column_type="Calc[TSS Customer Refusals]", output_type="Number", format_string="." }, { name="% TSS Refusals", column_type="Calc[% TSS Refusals]", output_type="Number" }, { name="TSS Eligible for Physical Connectivity", column_type="Calc[TSS Eligible for Physical Connectivity]", output_type="Number", format_string="." }, { name="TSS Boxes with Physical Connectivty", column_type="Calc[TSS Boxes with Physical Connectivty]", output_type="Number", format_string="." }, { name="% TSS Physical Connectivity", column_type="Calc[% TSS Physical Connectivity]", output_type="Number" } }, dim_cols={ { name="Model", column_type="Dimension[Model]", output_type="None" }, { name="Model", column_type="Dimension[Model]", output_type="None" }, { name="Connect In Type", column_type="Dimension[Connect In Type]", output_type="None" }, { name="Connect Home Type", column_type="Dimension[Connect Home Type]", output_type="None" }, { name="SymmConnect Enabled", column_type="Dimension[SymmConnect Enabled]", output_type="None" }, { name="Theater", column_type="Dimension[Theater]", output_type="None" }, { name="Division", column_type="Dimension[Division]", output_type="None" }, { name="Region", column_type="Dimension[Region]", output_type="None" }, { name="Sales Order Number", column_type="Dimension[Sales Order Number]", output_type="None" }, { name="Product Item Family", column_type="Dimension[Product Item Family]", output_type="None" }, { name="Item Serial Number", column_type="Dimension[Item Serial Number]", output_type="None" }, { name="Sales Order Deal Number", column_type="Dimension[Sales Order Deal Number]", output_type="None" }, { name="Item Install Date", column_type="Dimension[Item Install Date]", output_type="None" }, { name="SYR Last Dial Home Date", column_type="Dimension[SYR Last Dial Home Date]", output_type="None" }, { name="Maintained By Group", column_type="Dimension[Maintained By Group]", output_type="None" }, { name="PS Flag", column_type="Dimension[PS Flag]", output_type="None" }, { name="Connect Home Refusal Reason", column_type="Dimension[Connect Home Refusal Reason]", output_type="None", col_width=177 }, { name="Cust Name", column_type="Dimension[Cust Name]", output_type="None" }, { name="Sales Order Channel Type", column_type="Dimension[Sales Order Channel Type]", output_type="None" }, { name="Sales Order Type", column_type="Dimension[Sales Order Type]", output_type="None" }, { name="Part Model Key", column_type="Dimension[Part Model Key]", output_type="None" }, { name="Ship Date", column_type="Dimension[Ship Date]", output_type="None" }, { name="Model Number", column_type="Dimension[Model Number]", output_type="None" }, { name="Item Description", column_type="Dimension[Item Description]", output_type="None" }, { name="Customer Classification", column_type="Dimension[Customer Classification]", output_type="None" }, { name="CS Customer Name", column_type="Dimension[CS Customer Name]", output_type="None" }, { name="Install At Customer Number", column_type="Dimension[Install At Customer Number]", output_type="None" }, { name="Install at Country Name", column_type="Dimension[Install at Country Name]", output_type="None" }, { name="TLA Serial Number", column_type="Dimension[TLA Serial Number]", output_type="None" }, { name="Product Version", column_type="Dimension[Product Version]", output_type="None" }, { name="Avalanche Flag", column_type="Dimension[Avalanche Flag]", output_type="None" }, { name="Product Family", column_type="Dimension[Product Family]", output_type="None" }, { name="Project Number", column_type="Dimension[Project Number]", output_type="None" }, { name="PROJECT_STATUS", column_type="Dimension[PROJECT_STATUS]", output_type="None" } }, Available_Columns={ "Total TSS installs", "TSS Valid Connectivity Records", "% TSS Connectivity Record", "TSS Not Applicable", "TSS Customer Refusals", "% TSS Refusals", "TSS Eligible for Physical Connectivity", "TSS Boxes with Physical Connectivty", "% TSS Physical Connectivity", "Total Installs", "All Boxes with Valid Connectivty Record", "% All Connectivity Record", "Overall Refusals", "Overall Refusals %", "All Eligible for Physical Connectivty", "Boxes with Physical Connectivity", "% All with Physical Conectivity" }, Remaining_columns={ { name="Total Installs", column_type="Calc[Total Installs]", output_type="Number", format_string="." }, { name="All Boxes with Valid Connectivty Record", column_type="Calc[All Boxes with Valid Connectivty Record]", output_type="Number", format_string="." }, { name="% All Connectivity Record", column_type="Calc[% All Connectivity Record]", output_type="Number" }, { name="Overall Refusals", column_type="Calc[Overall Refusals]", output_type="Number", format_string="." }, { name="Overall Refusals %", column_type="Calc[Overall Refusals %]", output_type="Number" }, { name="All Eligible for Physical Connectivty", column_type="Calc[All Eligible for Physical Connectivty]", output_type="Number" }, { name="Boxes with Physical Connectivity", column_type="Calc[Boxes with Physical Connectivity]", output_type="Number" }, { name="% All with Physical Conectivity", column_type="Calc[% All with Physical Conectivity]", output_type="Number" } }, calcs={ { name="Total TSS installs", definition="Total[Total TSS installs]", ts_flag="Not TS Calc" }, { name="TSS Valid Connectivity Records", definition="Total[PS Boxes w/ valid connectivity record (1=yes)]", ts_flag="Not TS Calc" }, { name="% TSS Connectivity Record", definition="Total[PS Boxes w/ valid connectivity record (1=yes)] /Total[Total TSS installs]", ts_flag="Not TS Calc" }, { name="TSS Not Applicable", definition="Total[Bozes w/ valid connectivity record (1=yes)]-Total[Boxes Eligible (1=yes)]-Total[TSS Refusals]", ts_flag="Not TS Calc" }, { name="TSS Customer Refusals", definition="Total[TSS Refusals]", ts_flag="Not TS Calc" }, { name="% TSS Refusals", definition="Total[TSS Refusals]/Total[PS Boxes w/ valid connectivity record (1=yes)]", ts_flag="Not TS Calc" }, { name="TSS Eligible for Physical Connectivity", definition="Total[TSS Eligible]-Total[Exception]", ts_flag="Not TS Calc" }, { name="TSS Boxes with Physical Connectivty", definition="Total[PS Physical Connectivity] - Total[PS Physical Connectivity, SymmConnect Enabled=\"Capable not enabled\"]", ts_flag="Not TS Calc" }, { name="% TSS Physical Connectivity", definition="Total[Boxes w/ phys conn]/Total[Boxes Eligible (1=yes)]", ts_flag="Not TS Calc" }, { name="Total Installs", definition="Total[Total Installs]", ts_flag="Not TS Calc" }, { name="All Boxes with Valid Connectivty Record", definition="Total[Bozes w/ valid connectivity record (1=yes)]", ts_flag="Not TS Calc" }, { name="% All Connectivity Record", definition="Total[Bozes w/ valid connectivity record (1=yes)]/Total[Total Installs]", ts_flag="Not TS Calc" }, { name="Overall Refusals", definition="Total[Overall Refusals]", ts_flag="Not TS Calc" }, { name="Overall Refusals %", definition="Total[Overall Refusals]/Total[Bozes w/ valid connectivity record (1=yes)]", ts_flag="Not TS Calc" }, { name="All Eligible for Physical Connectivty", definition="Total[Boxes Eligible (1=yes)]-Total[Exception]", ts_flag="Not TS Calc" }, { name="Boxes with Physical Connectivity", definition="Total[Boxes w/ phys conn]-Total[Boxes w/ phys conn,SymmConnect Enabled=\"Capable not enabled\"]", ts_flag="Not TS Calc" }, { name="% All with Physical Conectivity", definition="Total[Boxes w/ phys conn]/Total[Boxes Eligible (1=yes)]", ts_flag="Not TS Calc" } }, merge_type="consolidate", merge_dbs={ { dbname="connectivityallproducts.mdl", diveline_dbname="/DI_PSREPORTING/connectivityallproducts.mdl" } }, skip_constant_columns="FALSE", categories={ { name="Geography", dimensions={ "Theater", "Division", "Region", "Install at Country Name" } }, { name="Mappings and Flags", dimensions={ "Connect Home Type", "Connect In Type", "SymmConnect Enabled", "Connect Home Refusal Reason", "Sales Order Channel Type", "Maintained By Group", "Customer Installable", "PS Flag", "Top Level Flag", "Avalanche Flag" } }, { name="Product Information", dimensions={ "Product Family", "Product Item Family", "Product Version", "Item Description" } }, { name="Sales Order Info", dimensions={ "Sales Order Deal Number", "Sales Order Number", "Sales Order Type" } }, { name="Dates", dimensions={ "Item Install Date", "Ship Date", "SYR Last Dial Home Date" } }, { name="Details", dimensions={ "Item Serial Number", "TLA Serial Number", "Part Model Key", "Model Number" } }, { name="Customer Infor", dimensions={ "CS Customer Name", "Install At Customer Number", "Customer Classification", "Cust Name" } }, { name="Other Dimensions", dimensions={ "Model" } } }, Maintain_Category_Order="FALSE", popup_info="false" } } };

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  • Can this Query be corrected or different table structure needed? (database dumps provided)

    - by sandeepan
    This is a bit lengthy but I have provided sufficient details and kept things very clear. Please see if you can help. (I will surely accept answer if it solves my problem) I am sure a person experienced with this can surely help or suggest me to decide the tables structure. About the system:- There are tutors who create classes A tags based search approach is being followed Tag relations are created/edited when new tutors registers/edits profile data and when tutors create classes (this makes tutors and classes searcheable).For simplicity, let us consider only tutor name and class name are the fields which are matched against search keywords. In this example, I am considering - tutor "Sandeepan Nath" has created a class called "first class" tutor "Bob Cratchit" has created a class called "new class" Desired search results- AND logic to be appied on the search keywords and match against class and tutor data(class name + tutor name), in other words, All those classes be shown such that all the search terms are present in the class name or its tutor name. Example to be clear - Searching "first class" returns class with id_wc = 1. Working Searching "Sandeepan class" should also return class with id_wc = 1. Not working in System 2. Problem with profile editing and searching To tell in one sentence, I am facing a conflict between the ease of profile edition (edition of tag relations when tutor profiles are edited) and the ease of search logic. In the beginning, we had one table structure and search was easy but tag edition logic was very clumsy and unmaintainable(Check System 1 in the section below) . So we created separate tag relations tables to make profile edition simpler but search has become difficult. Please dump the tables so that you can run the search query I have given below and see the results. System 1 (previous system - search easy - profile edition difficult):- Only one table called All_Tag_Relations table had the all the tag relations. The tags table below is common to both systems 1 and 2. CREATE TABLE IF NOT EXISTS `all_tag_relations` ( `id_tag_rel` int(10) NOT NULL AUTO_INCREMENT, `id_tag` int(10) unsigned NOT NULL DEFAULT '0', `id_tutor` int(10) DEFAULT NULL, `id_wc` int(10) unsigned DEFAULT NULL, PRIMARY KEY (`id_tag_rel`), KEY `All_Tag_Relations_FKIndex1` (`id_tag`), KEY `id_wc` (`id_wc`), KEY `id_tag` (`id_tag`) ) ENGINE=InnoDB DEFAULT CHARSET=latin1; INSERT INTO `all_tag_relations` (`id_tag_rel`, `id_tag`, `id_tutor`, `id_wc`) VALUES (1, 1, 1, NULL), (2, 2, 1, NULL), (3, 1, 1, 1), (4, 2, 1, 1), (5, 3, 1, 1), (6, 4, 1, 1), (7, 6, 2, NULL), (8, 7, 2, NULL), (9, 6, 2, 2), (10, 7, 2, 2), (11, 5, 2, 2), (12, 4, 2, 2); CREATE TABLE IF NOT EXISTS `tags` ( `id_tag` int(10) unsigned NOT NULL AUTO_INCREMENT, `tag` varchar(255) DEFAULT NULL, PRIMARY KEY (`id_tag`), UNIQUE KEY `tag` (`tag`), KEY `id_tag` (`id_tag`), KEY `tag_2` (`tag`), KEY `tag_3` (`tag`), KEY `tag_4` (`tag`), FULLTEXT KEY `tag_5` (`tag`) ) ENGINE=MyISAM DEFAULT CHARSET=latin1 AUTO_INCREMENT=8 ; INSERT INTO `tags` (`id_tag`, `tag`) VALUES (1, 'Sandeepan'), (2, 'Nath'), (3, 'first'), (4, 'class'), (5, 'new'), (6, 'Bob'), (7, 'Cratchit'); Please note that for every class, the tag rels of its tutor have to be duplicated. Example, for class with id_wc=1, the tag rel records with id_tag_rel = 3 and 4 are actually extras if you compare with the tag rel records with id_tag_rel = 1 and 2. System 2 (present system - profile edition easy, search difficult) Two separate tables Tutors_Tag_Relations and Webclasses_Tag_Relations have the corresponding tag relations data (Please dump into a separate database)- CREATE TABLE IF NOT EXISTS `tutors_tag_relations` ( `id_tag_rel` int(10) NOT NULL AUTO_INCREMENT, `id_tag` int(10) unsigned NOT NULL DEFAULT '0', `id_tutor` int(10) DEFAULT NULL, PRIMARY KEY (`id_tag_rel`), KEY `All_Tag_Relations_FKIndex1` (`id_tag`), KEY `id_tag` (`id_tag`) ) ENGINE=InnoDB DEFAULT CHARSET=latin1; INSERT INTO `tutors_tag_relations` (`id_tag_rel`, `id_tag`, `id_tutor`) VALUES (1, 1, 1), (2, 2, 1), (3, 6, 2), (4, 7, 2); CREATE TABLE IF NOT EXISTS `webclasses_tag_relations` ( `id_tag_rel` int(10) NOT NULL AUTO_INCREMENT, `id_tag` int(10) unsigned NOT NULL DEFAULT '0', `id_tutor` int(10) DEFAULT NULL, `id_wc` int(10) DEFAULT NULL, PRIMARY KEY (`id_tag_rel`), KEY `webclasses_Tag_Relations_FKIndex1` (`id_tag`), KEY `id_wc` (`id_wc`), KEY `id_tag` (`id_tag`) ) ENGINE=InnoDB DEFAULT CHARSET=latin1; INSERT INTO `webclasses_tag_relations` (`id_tag_rel`, `id_tag`, `id_tutor`, `id_wc`) VALUES (1, 3, 1, 1), (2, 4, 1, 1), (3, 5, 2, 2), (4, 4, 2, 2); CREATE TABLE IF NOT EXISTS `tags` ( `id_tag` int(10) unsigned NOT NULL AUTO_INCREMENT, `tag` varchar(255) DEFAULT NULL, PRIMARY KEY (`id_tag`), UNIQUE KEY `tag` (`tag`), KEY `id_tag` (`id_tag`), KEY `tag_2` (`tag`), KEY `tag_3` (`tag`), KEY `tag_4` (`tag`), FULLTEXT KEY `tag_5` (`tag`) ) ENGINE=MyISAM DEFAULT CHARSET=latin1 AUTO_INCREMENT=8 ; INSERT INTO `tags` (`id_tag`, `tag`) VALUES (1, 'Sandeepan'), (2, 'Nath'), (3, 'first'), (4, 'class'), (5, 'new'), (6, 'Bob'), (7, 'Cratchit'); CREATE TABLE IF NOT EXISTS `all_tag_relations` ( `id_tag_rel` int(10) NOT NULL AUTO_INCREMENT, `id_tag` int(10) unsigned NOT NULL DEFAULT '0', `id_tutor` int(10) DEFAULT NULL, `id_wc` int(10) unsigned DEFAULT NULL, PRIMARY KEY (`id_tag_rel`), KEY `All_Tag_Relations_FKIndex1` (`id_tag`), KEY `id_wc` (`id_wc`) ) ENGINE=InnoDB DEFAULT CHARSET=latin1; insert into All_Tag_Relations select NULL,id_tag,id_tutor,NULL from Tutors_Tag_Relations; insert into All_Tag_Relations select NULL,id_tag,id_tutor,id_wc from Webclasses_Tag_Relations; Here you can see how easily tutor first name can be edited only in one place. But search has become really difficult, so on being advised to use a Temporary table, I am creating one at every search request, then dumping all the necessary data and then searching from it, I am creating this All_Tag_Relations table at search run time. Here I am just dumping all the data from the two tables Tutors_Tag_Relations and Webclasses_Tag_Relations. But, I am still not able to get classes if I search with tutor name This is the query which searches "first class". Running them on both the systems shows correct results (returns the class with id_wc = 1). SELECT wtagrels.id_wc,SUM(DISTINCT( wtagrels.id_tag =3)) AS key_1_total_matches, SUM(DISTINCT( wtagrels.id_tag =4)) AS key_2_total_matches FROM all_tag_relations AS wtagrels WHERE ( wtagrels.id_tag =3 OR wtagrels.id_tag =4 ) GROUP BY wtagrels.id_wc HAVING key_1_total_matches = 1 AND key_2_total_matches = 1 LIMIT 0, 20 But, searching for "Sandeepan class" works only with the 1st system Here is the query which searches "Sandeepan class" SELECT wtagrels.id_wc,SUM(DISTINCT( wtagrels.id_tag =1)) AS key_1_total_matches, SUM(DISTINCT( wtagrels.id_tag =4)) AS key_2_total_matches FROM all_tag_relations AS wtagrels WHERE ( wtagrels.id_tag =1 OR wtagrels.id_tag =4 ) GROUP BY wtagrels.id_wc HAVING key_1_total_matches = 1 AND key_2_total_matches = 1 LIMIT 0, 20 Can anybody alter this query and somehow do a proper join or something to get correct results. That solves my problem in a nice way. As you can figure out, the reason why it does not work in system 2 is that in system 1, for every class, one additional tag relation linking class and tutor name is present. e.g. for class first class, (records with id_tag_rel 3 and 4) which returns the class on searching with tutor name. So, you see the trade-off between the search and profile edition difficulty with the two systems. How do I overcome both. I have to reach a conclusion soon. So far my reasoning is it is definitely not good from a code maintainability point of view to follow the single tag rel table structure of system one, because in a real system while editing a field like "tutor qualifications", there can be as many records in tag rels table as there are words in qualification of a tutor (one word in a field = one tag relation). Now suppose a tutor has 100 classes. When he edits his qualification, all the tag rel rows corresponding to him are deleted and then as many copies are to be created (as per the new qualification data) as there are classes. This becomes particularly difficult if later more searcheable fields are added. The code cannot be robust. Is the best solution to follow system 2 (edition has to be in one table - no extra work for each and every class) and somehow re-create the all_tag_relations table like system 1 (from the tables tutor_tag_relations and webclasses_tag_relations), creating the extra tutor tag rels for each and every class by a tutor (which is currently missing in system 2's temporary all_tag_relations table). That would be a time consuming logic script. I doubt that table can be recreated without resorting to PHP sript (mysql alone cannot do that). But the problem is that running all this at search time will make search definitely slow. So, how do such systems work? How are such situations handled? I thought about we can run a cron which initiates that PHP script, say every 1 minute and replaces the existing all_tag_relations table as per new tag rels from tutor_tag_relations and webclasses_tag_relations (replaces means creates a new table, deletes the original and renames the new one as all_tag_relations, otherwise search won't work during that period- or is there any better way to that?). Anyway, the result would be that any changes by tutors will reflect in search in the next 1 minute and not immediately. An alternateve would be to initate that PHP script every time a tutor edits his profile. But here again, since many users may edit their profiles concurrently, will the creation of so many tables be a burden and can mysql make the server slow? Any help would be appreciated and working solution will be accepted as answer. Thanks, Sandeepan

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  • Can this Query can be corrected or different table structure needed? (question is clear, detailed, d

    - by sandeepan
    This is a bit lengthy but I have provided sufficient details and kept things very clear. Please see if you can help. (I will surely accept answer if it solves my problem) I am sure a person experienced with this can surely help or suggest me to decide the tables structure. About the system:- There are tutors who create classes A tags based search approach is being followed Tag relations are created/edited when new tutors registers/edits profile data and when tutors create classes (this makes tutors and classes searcheable).For simplicity, let us consider only tutor name and class name are the fields which are matched against search keywords. In this example, I am considering - tutor "Sandeepan Nath" has created a class called "first class" tutor "Bob Cratchit" has created a class called "new class" Desired search results- AND logic to be appied on the search keywords and match against class and tutor data(class name + tutor name), in other words, All those classes be shown such that all the search terms are present in the class name or its tutor name. Example to be clear - Searching "first class" returns class with id_wc = 1. Working Searching "Sandeepan class" should also return class with id_wc = 1. Not working in System 2. Problem with profile editing and searching To tell in one sentence, I am facing a conflict between the ease of profile edition (edition of tag relations when tutor profiles are edited) and the ease of search logic. In the beginning, we had one table structure and search was easy but tag edition logic was very clumsy and unmaintainable(Check System 1 in the section below) . So we created separate tag relations tables to make profile edition simpler but search has become difficult. Please dump the tables so that you can run the search query I have given below and see the results. System 1 (previous system - search easy - profile edition difficult):- Only one table called All_Tag_Relations table had the all the tag relations. The tags table below is common to both systems 1 and 2. CREATE TABLE IF NOT EXISTS `all_tag_relations` ( `id_tag_rel` int(10) NOT NULL AUTO_INCREMENT, `id_tag` int(10) unsigned NOT NULL DEFAULT '0', `id_tutor` int(10) DEFAULT NULL, `id_wc` int(10) unsigned DEFAULT NULL, PRIMARY KEY (`id_tag_rel`), KEY `All_Tag_Relations_FKIndex1` (`id_tag`), KEY `id_wc` (`id_wc`), KEY `id_tag` (`id_tag`) ) ENGINE=InnoDB DEFAULT CHARSET=latin1; INSERT INTO `all_tag_relations` (`id_tag_rel`, `id_tag`, `id_tutor`, `id_wc`) VALUES (1, 1, 1, NULL), (2, 2, 1, NULL), (3, 1, 1, 1), (4, 2, 1, 1), (5, 3, 1, 1), (6, 4, 1, 1), (7, 6, 2, NULL), (8, 7, 2, NULL), (9, 6, 2, 2), (10, 7, 2, 2), (11, 5, 2, 2), (12, 4, 2, 2); CREATE TABLE IF NOT EXISTS `tags` ( `id_tag` int(10) unsigned NOT NULL AUTO_INCREMENT, `tag` varchar(255) DEFAULT NULL, PRIMARY KEY (`id_tag`), UNIQUE KEY `tag` (`tag`), KEY `id_tag` (`id_tag`), KEY `tag_2` (`tag`), KEY `tag_3` (`tag`), KEY `tag_4` (`tag`), FULLTEXT KEY `tag_5` (`tag`) ) ENGINE=MyISAM DEFAULT CHARSET=latin1 AUTO_INCREMENT=8 ; INSERT INTO `tags` (`id_tag`, `tag`) VALUES (1, 'Sandeepan'), (2, 'Nath'), (3, 'first'), (4, 'class'), (5, 'new'), (6, 'Bob'), (7, 'Cratchit'); Please note that for every class, the tag rels of its tutor have to be duplicated. Example, for class with id_wc=1, the tag rel records with id_tag_rel = 3 and 4 are actually extras if you compare with the tag rel records with id_tag_rel = 1 and 2. System 2 (present system - profile edition easy, search difficult) Two separate tables Tutors_Tag_Relations and Webclasses_Tag_Relations have the corresponding tag relations data (Please dump into a separate database)- CREATE TABLE IF NOT EXISTS `tutors_tag_relations` ( `id_tag_rel` int(10) NOT NULL AUTO_INCREMENT, `id_tag` int(10) unsigned NOT NULL DEFAULT '0', `id_tutor` int(10) DEFAULT NULL, PRIMARY KEY (`id_tag_rel`), KEY `All_Tag_Relations_FKIndex1` (`id_tag`), KEY `id_tag` (`id_tag`) ) ENGINE=InnoDB DEFAULT CHARSET=latin1; INSERT INTO `tutors_tag_relations` (`id_tag_rel`, `id_tag`, `id_tutor`) VALUES (1, 1, 1), (2, 2, 1), (3, 6, 2), (4, 7, 2); CREATE TABLE IF NOT EXISTS `webclasses_tag_relations` ( `id_tag_rel` int(10) NOT NULL AUTO_INCREMENT, `id_tag` int(10) unsigned NOT NULL DEFAULT '0', `id_tutor` int(10) DEFAULT NULL, `id_wc` int(10) DEFAULT NULL, PRIMARY KEY (`id_tag_rel`), KEY `webclasses_Tag_Relations_FKIndex1` (`id_tag`), KEY `id_wc` (`id_wc`), KEY `id_tag` (`id_tag`) ) ENGINE=InnoDB DEFAULT CHARSET=latin1; INSERT INTO `webclasses_tag_relations` (`id_tag_rel`, `id_tag`, `id_tutor`, `id_wc`) VALUES (1, 3, 1, 1), (2, 4, 1, 1), (3, 5, 2, 2), (4, 4, 2, 2); CREATE TABLE IF NOT EXISTS `tags` ( `id_tag` int(10) unsigned NOT NULL AUTO_INCREMENT, `tag` varchar(255) DEFAULT NULL, PRIMARY KEY (`id_tag`), UNIQUE KEY `tag` (`tag`), KEY `id_tag` (`id_tag`), KEY `tag_2` (`tag`), KEY `tag_3` (`tag`), KEY `tag_4` (`tag`), FULLTEXT KEY `tag_5` (`tag`) ) ENGINE=MyISAM DEFAULT CHARSET=latin1 AUTO_INCREMENT=8 ; INSERT INTO `tags` (`id_tag`, `tag`) VALUES (1, 'Sandeepan'), (2, 'Nath'), (3, 'first'), (4, 'class'), (5, 'new'), (6, 'Bob'), (7, 'Cratchit'); CREATE TABLE IF NOT EXISTS `all_tag_relations` ( `id_tag_rel` int(10) NOT NULL AUTO_INCREMENT, `id_tag` int(10) unsigned NOT NULL DEFAULT '0', `id_tutor` int(10) DEFAULT NULL, `id_wc` int(10) unsigned DEFAULT NULL, PRIMARY KEY (`id_tag_rel`), KEY `All_Tag_Relations_FKIndex1` (`id_tag`), KEY `id_wc` (`id_wc`) ) ENGINE=InnoDB DEFAULT CHARSET=latin1; insert into All_Tag_Relations select NULL,id_tag,id_tutor,NULL from Tutors_Tag_Relations; insert into All_Tag_Relations select NULL,id_tag,id_tutor,id_wc from Webclasses_Tag_Relations; Here you can see how easily tutor first name can be edited only in one place. But search has become really difficult, so on being advised to use a Temporary table, I am creating one at every search request, then dumping all the necessary data and then searching from it, I am creating this All_Tag_Relations table at search run time. Here I am just dumping all the data from the two tables Tutors_Tag_Relations and Webclasses_Tag_Relations. But, I am still not able to get classes if I search with tutor name This is the query which searches "first class". Running them on both the systems shows correct results (returns the class with id_wc = 1). SELECT wtagrels.id_wc,SUM(DISTINCT( wtagrels.id_tag =3)) AS key_1_total_matches, SUM(DISTINCT( wtagrels.id_tag =4)) AS key_2_total_matches FROM all_tag_relations AS wtagrels WHERE ( wtagrels.id_tag =3 OR wtagrels.id_tag =4 ) GROUP BY wtagrels.id_wc HAVING key_1_total_matches = 1 AND key_2_total_matches = 1 LIMIT 0, 20 But, searching for "Sandeepan class" works only with the 1st system Here is the query which searches "Sandeepan class" SELECT wtagrels.id_wc,SUM(DISTINCT( wtagrels.id_tag =1)) AS key_1_total_matches, SUM(DISTINCT( wtagrels.id_tag =4)) AS key_2_total_matches FROM all_tag_relations AS wtagrels WHERE ( wtagrels.id_tag =1 OR wtagrels.id_tag =4 ) GROUP BY wtagrels.id_wc HAVING key_1_total_matches = 1 AND key_2_total_matches = 1 LIMIT 0, 20 Can anybody alter this query and somehow do a proper join or something to get correct results. That solves my problem in a nice way. As you can figure out, the reason why it does not work in system 2 is that in system 1, for every class, one additional tag relation linking class and tutor name is present. e.g. for class first class, (records with id_tag_rel 3 and 4) which returns the class on searching with tutor name. So, you see the trade-off between the search and profile edition difficulty with the two systems. How do I overcome both. I have to reach a conclusion soon. So far my reasoning is it is definitely not good from a code maintainability point of view to follow the single tag rel table structure of system one, because in a real system while editing a field like "tutor qualifications", there can be as many records in tag rels table as there are words in qualification of a tutor (one word in a field = one tag relation). Now suppose a tutor has 100 classes. When he edits his qualification, all the tag rel rows corresponding to him are deleted and then as many copies are to be created (as per the new qualification data) as there are classes. This becomes particularly difficult if later more searcheable fields are added. The code cannot be robust. Is the best solution to follow system 2 (edition has to be in one table - no extra work for each and every class) and somehow re-create the all_tag_relations table like system 1 (from the tables tutor_tag_relations and webclasses_tag_relations), creating the extra tutor tag rels for each and every class by a tutor (which is currently missing in system 2's temporary all_tag_relations table). That would be a time consuming logic script. I doubt that table can be recreated without resorting to PHP sript (mysql alone cannot do that). But the problem is that running all this at search time will make search definitely slow. So, how do such systems work? How are such situations handled? I thought about we can run a cron which initiates that PHP script, say every 1 minute and replaces the existing all_tag_relations table as per new tag rels from tutor_tag_relations and webclasses_tag_relations (replaces means creates a new table, deletes the original and renames the new one as all_tag_relations, otherwise search won't work during that period- or is there any better way to that?). Anyway, the result would be that any changes by tutors will reflect in search in the next 1 minute and not immediately. An alternateve would be to initate that PHP script every time a tutor edits his profile. But here again, since many users may edit their profiles concurrently, will the creation of so many tables be a burden and can mysql make the server slow? Any help would be appreciated and working solution will be accepted as answer. Thanks, Sandeepan

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  • MYSQL LIMIT not working as expected - Java

    - by Sirish
    I have this weird problem in java when trying to fetch records from MYSql database by using the limit function in the query. Not sure what went wrong or did wrong, this query is giving me a hard time. Issue - When I run this query through my java program it returns all the records and not limiting the records to 10 as given in the limit. The same query when ran in MYSql command line, it execute very well and fetches me only 10 recrods. Below is the java code and query. Any help or support is appreciated.! Java code - public UserVO getApplUserDetailsList(UserVO userVO) throws CAPDAOException { List<UserVO> returnList = null; String methodName = "getApplUserDetails()"; Session session = null; String queryString = null; Transaction transaction = null; PreparedStatement ps = null; ResultSet rs = null; if(userVO == null) { logger.writeToTivoliAlertLog(className, CAPConstants.ERROR, methodName, null, "userVO returned null. Busines validation error.!", null); throw new CAPDAOException("userVO returned null. Busines validation error.!",CAPException.BUSINESS_VALIDATION_ERROR_SECURITY); } try { returnList = new ArrayList<UserVO>(); System.out.println(""); String appusr = userVO.getAppUsrNm(); session = getSession(); transaction = session.beginTransaction(); if(userVO.getAppUsrRoleCd()!=null && !userVO.getAppUsrRoleCd().trim().equalsIgnoreCase(CAPConstants.DEFAULT_DROPDOWN_VALUE)){ queryString = "SELECT " + "APPL_USR_ID,APPL_USR_NM,APPL_USR_FRST_NM, " + "APPL_USR_LST_NM,ACCESS_ROLE_CD " + "FROM APPL_USR " + "WHERE " + "APPL_USR_NM LIKE ?"+ " AND APPL_USR_FRST_NM LIKE ?"+ " AND APPL_USR_LST_NM LIKE ?"+ " AND ACCESS_ROLE_CD = ?"+ " AND APPL_USR_ID != ?"; ps = session.connection().prepareStatement(queryString); ps.setString(1,userVO.getAppUsrNm()+CAPConstants.PERCENTILE_SYMBOL); ps.setString(2,userVO.getAppUsrFirstNm()+CAPConstants.PERCENTILE_SYMBOL); ps.setString(3,userVO.getAppUsrLastNm()+CAPConstants.PERCENTILE_SYMBOL); ps.setString(4,userVO.getAppUsrRoleCd()); ps.setInt(5, 1); } else { queryString = "SELECT " + "APPL_USR_ID,APPL_USR_NM,APPL_USR_FRST_NM, " + "APPL_USR_LST_NM,ACCESS_ROLE_CD " + "FROM APPL_USR " + "WHERE " + "APPL_USR_NM LIKE ?"+ " AND APPL_USR_FRST_NM LIKE ?"+ " AND APPL_USR_LST_NM LIKE ?"+ " AND APPL_USR_ID != ?"; ps = session.connection().prepareStatement(queryString); ps.setString(1,userVO.getAppUsrNm()+CAPConstants.PERCENTILE_SYMBOL); ps.setString(2,userVO.getAppUsrFirstNm()+CAPConstants.PERCENTILE_SYMBOL); ps.setString(3,userVO.getAppUsrLastNm()+CAPConstants.PERCENTILE_SYMBOL); ps.setInt(4, 1); } if(userVO.getQueryAction()!=null && userVO.getQueryAction().equals(CAPConstants.GET_DATA)) queryString += " ORDER BY APPL_USR_ID LIMIT " + userVO.getPAGE_MIN_LIMIT() + ", " + userVO.getPAGE_MAX_LIMIT(); else queryString += " ORDER BY APPL_USR_ID"; rs = ps.executeQuery(); if(userVO.getQueryAction()!=null && userVO.getQueryAction().equals(CAPConstants.GET_DATA)) { int tempCOunt = 0; while(rs!=null && rs.next()) { tempCOunt ++; UserVO returnVO = new UserVO(); returnVO.setAppUsrId(rs.getInt("APPL_USR_ID")); returnVO.setAppUsrNm(rs.getString("APPL_USR_NM")); returnVO.setAppUsrFirstNm(rs.getString("APPL_USR_FRST_NM")); returnVO.setAppUsrLastNm(rs.getString("APPL_USR_LST_NM")); if (rs.getString("ACCESS_ROLE_CD")!=null && rs.getString("ACCESS_ROLE_CD").trim().equalsIgnoreCase(CAPConstants.ADMINISTRATOR_ROLE_CD)) returnVO.setApplicationLevelRole("Administrator"); else if (rs.getString("ACCESS_ROLE_CD")!=null && rs.getString("ACCESS_ROLE_CD").trim().equalsIgnoreCase(CAPConstants.MAINTAINER_ROLE_CD)) returnVO.setApplicationLevelRole("Maintainer"); else if (rs.getString("ACCESS_ROLE_CD")!=null && rs.getString("ACCESS_ROLE_CD").trim().equalsIgnoreCase(CAPConstants.VIEWER_ROLE_CD)) returnVO.setApplicationLevelRole("Viewer"); else returnVO.setApplicationLevelRole("None"); returnList.add(returnVO); } System.out.println("Count >>>>>>>>>>>>>>>>>>> "+tempCOunt); userVO.setReturnListFromDB(returnList); } else { int rowcount = 0; if (rs.last()) { rowcount = rs.getRow(); rs.beforeFirst(); // not rs.first() because the rs.next() below will move on, missing the first element } userVO.setTotalRecordCount(rowcount); System.out.println("Total count of the records to be used for pagination >> "+rowcount); rowcount = 0; while(rs!=null && rs.next()) { rowcount ++; UserVO returnVO = new UserVO(); returnVO.setAppUsrId(rs.getInt("APPL_USR_ID")); returnVO.setAppUsrNm(rs.getString("APPL_USR_NM")); returnVO.setAppUsrFirstNm(rs.getString("APPL_USR_FRST_NM")); returnVO.setAppUsrLastNm(rs.getString("APPL_USR_LST_NM")); if (rs.getString("ACCESS_ROLE_CD")!=null && rs.getString("ACCESS_ROLE_CD").trim().equalsIgnoreCase(CAPConstants.ADMINISTRATOR_ROLE_CD)) returnVO.setApplicationLevelRole("Administrator"); else if (rs.getString("ACCESS_ROLE_CD")!=null && rs.getString("ACCESS_ROLE_CD").trim().equalsIgnoreCase(CAPConstants.MAINTAINER_ROLE_CD)) returnVO.setApplicationLevelRole("Maintainer"); else if (rs.getString("ACCESS_ROLE_CD")!=null && rs.getString("ACCESS_ROLE_CD").trim().equalsIgnoreCase(CAPConstants.VIEWER_ROLE_CD)) returnVO.setApplicationLevelRole("Viewer"); else returnVO.setApplicationLevelRole("None"); returnList.add(returnVO); System.out.println("Row count >>"+rowcount); if(rowcount == CAPConstants.PAGINATION_MAX_VALUE) break; } rowcount = 0; userVO.setReturnListFromDB(returnList); } System.out.println("returnList >>"+returnList); return userVO; } catch (Throwable e) { e.printStackTrace(); logger.writeToTivoliAlertLog(className, CAPConstants.ERROR, methodName, userVO.getAppUsrNm(), "Error occured while trying to fetch application user details. Printing stack trace to the log for analysis..", e); throw new CAPDAOException("Error occured while trying to fetch application user details.",CAPException.SPEXECUTION_ERROR_CODE); } finally{ closeTransactionAndSession(session,transaction); } } MYSQL Query - SELECT APPL_USR_ID,APPL_USR_NM,APPL_USR_FRST_NM, APPL_USR_LST_NM,ACCESS_ROLE_CD FROM APPL_USR WHERE APPL_USR_NM LIKE '%' AND APPL_USR_FRST_NM LIKE '%' AND APPL_USR_LST_NM LIKE '%' AND APPL_USR_ID != 1 ORDER BY APPL_USR_ID LIMIT 10, 10

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  • wrong return value with jquery ajax and codeigniter

    - by matthew
    I do not know if this is specifically a jquery problem, actually I think it has to mostly do with my logic in the php code. What Im trying to do is make a voting system that when the user clicks on the vote up or vote down link in the web page, it triggers an ajax call to a php function that first updates the database with with the required value, on success of the database updating the another function is called just to get the required updated html for the that particular post that the user has voted on. (hope I havnt lost you). The problem I think deals with specifically with this one line of code. When I make the call it only returns the value of $row-beer_down and completly ignores everything else in that line. Funny thing is the same php code to display the html view works perfectly before the ajax function updates it. echo "<p>Score " . $row->beer_up + $row->beer_down . "</p>"; so here is the code to hope you can help as I have absolutely no idea how to fix this. here is the view file where it generates the page. This part is the query ajax function. <script type="text/javascript"> $(function() { $(".vote").click(function(){ var id = $(this).attr("id"); var name = $(this).attr("name"); var dataString = 'id='+ id ; var parent = $(this); if(name=='up') { $.ajax({ type: "POST", url: "http://127.0.0.1/CodeIgniter/blog/add_vote/" + id, data: dataString, cache: false, success: function(html) { //parent.html(html); $("." + id).load('http://127.0.0.1/CodeIgniter/blog/get_post/' + id).fadeIn("slow"); } }); } else { $.ajax({ type: "POST", url: "http://127.0.0.1/CodeIgniter/blog/minus_vote/" + id, data: dataString, cache: false, success: function(html) { //parent.html(html); $("." + id).load('http://127.0.0.1/CodeIgniter/blog/get_post/' + id).fadeIn("slow"); } }); } return false; }); }); </script> Here is the html and php part of the page to display the post. div id="post_container"> <?php //echo $this->table->generate($records); ?> <?php foreach($records->result() as $row) { ?> <?php echo "<div id=\"post\" class=\"" . $row->id . "\">"; ?> <h2><?php echo $row->id ?></h2> <?php echo "<img src=\"" . base_url() . $dir . $row->account_id . "/" . $row->file_name . "\">" ?> <p><?php echo $row->content ?></p> <p><?php echo $row->user_name ?> On <?php echo $row->time ?></p> <p>Score <?php echo $row->beer_up + $row->beer_down ?></p> <?php echo anchor('blog/add_vote/' . $row->id, 'Up Vote', array('class' => 'vote', 'id' => $row->id, 'name' => 'up')); echo anchor('blog/minus_vote/' . $row->id, 'Down Vote', array('class' => 'vote', 'id' => $row->id, 'name' => 'down')); echo anchor('blog/comments/' . $row->id, 'View Comments'); ?> </div> <?php } ?> here is the function the ajax calls when it is successfull: function get_post() { $this->db->where('id', $this->uri->segment(3)); $records = $this->db->get('post'); $dir = "/uploads/user_uploads/"; foreach($records->result() as $row) { echo "<div id=\"post\" class=\"" . $row->id . "\">"; echo "<h2>" . $row->id . "</h2>"; echo "<img src=\"" . base_url() . $dir . $row->account_id . "/" . $row->file_name . "\">"; echo "<p>" . $row->content . "</p>"; echo "<p>" . $row->user_name . " On " . $row->time . "</p>"; echo "<p>Score " . $row->beer_up + $row->beer_down . "</p>"; echo "<p>Up score" . $row->beer_up . "beer down" . $row->beer_down . "</p>"; echo anchor('blog/comments/' . $row->id, 'View Comments'); echo "</div>"; }

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  • Introduction to the ASP.NET Web API

    - by Stephen.Walther
    I am a huge fan of Ajax. If you want to create a great experience for the users of your website – regardless of whether you are building an ASP.NET MVC or an ASP.NET Web Forms site — then you need to use Ajax. Otherwise, you are just being cruel to your customers. We use Ajax extensively in several of the ASP.NET applications that my company, Superexpert.com, builds. We expose data from the server as JSON and use jQuery to retrieve and update that data from the browser. One challenge, when building an ASP.NET website, is deciding on which technology to use to expose JSON data from the server. For example, how do you expose a list of products from the server as JSON so you can retrieve the list of products with jQuery? You have a number of options (too many options) including ASMX Web services, WCF Web Services, ASHX Generic Handlers, WCF Data Services, and MVC controller actions. Fortunately, the world has just been simplified. With the release of ASP.NET 4 Beta, Microsoft has introduced a new technology for exposing JSON from the server named the ASP.NET Web API. You can use the ASP.NET Web API with both ASP.NET MVC and ASP.NET Web Forms applications. The goal of this blog post is to provide you with a brief overview of the features of the new ASP.NET Web API. You learn how to use the ASP.NET Web API to retrieve, insert, update, and delete database records with jQuery. We also discuss how you can perform form validation when using the Web API and use OData when using the Web API. Creating an ASP.NET Web API Controller The ASP.NET Web API exposes JSON data through a new type of controller called an API controller. You can add an API controller to an existing ASP.NET MVC 4 project through the standard Add Controller dialog box. Right-click your Controllers folder and select Add, Controller. In the dialog box, name your controller MovieController and select the Empty API controller template: A brand new API controller looks like this: using System; using System.Collections.Generic; using System.Linq; using System.Net.Http; using System.Web.Http; namespace MyWebAPIApp.Controllers { public class MovieController : ApiController { } } An API controller, unlike a standard MVC controller, derives from the base ApiController class instead of the base Controller class. Using jQuery to Retrieve, Insert, Update, and Delete Data Let’s create an Ajaxified Movie Database application. We’ll retrieve, insert, update, and delete movies using jQuery with the MovieController which we just created. Our Movie model class looks like this: namespace MyWebAPIApp.Models { public class Movie { public int Id { get; set; } public string Title { get; set; } public string Director { get; set; } } } Our application will consist of a single HTML page named Movies.html. We’ll place all of our jQuery code in the Movies.html page. Getting a Single Record with the ASP.NET Web API To support retrieving a single movie from the server, we need to add a Get method to our API controller: using System; using System.Collections.Generic; using System.Linq; using System.Net; using System.Net.Http; using System.Web.Http; using MyWebAPIApp.Models; namespace MyWebAPIApp.Controllers { public class MovieController : ApiController { public Movie GetMovie(int id) { // Return movie by id if (id == 1) { return new Movie { Id = 1, Title = "Star Wars", Director = "Lucas" }; } // Otherwise, movie was not found throw new HttpResponseException(HttpStatusCode.NotFound); } } } In the code above, the GetMovie() method accepts the Id of a movie. If the Id has the value 1 then the method returns the movie Star Wars. Otherwise, the method throws an exception and returns 404 Not Found HTTP status code. After building your project, you can invoke the MovieController.GetMovie() method by entering the following URL in your web browser address bar: http://localhost:[port]/api/movie/1 (You’ll need to enter the correct randomly generated port). In the URL api/movie/1, the first “api” segment indicates that this is a Web API route. The “movie” segment indicates that the MovieController should be invoked. You do not specify the name of the action. Instead, the HTTP method used to make the request – GET, POST, PUT, DELETE — is used to identify the action to invoke. The ASP.NET Web API uses different routing conventions than normal ASP.NET MVC controllers. When you make an HTTP GET request then any API controller method with a name that starts with “GET” is invoked. So, we could have called our API controller action GetPopcorn() instead of GetMovie() and it would still be invoked by the URL api/movie/1. The default route for the Web API is defined in the Global.asax file and it looks like this: routes.MapHttpRoute( name: "DefaultApi", routeTemplate: "api/{controller}/{id}", defaults: new { id = RouteParameter.Optional } ); We can invoke our GetMovie() controller action with the jQuery code in the following HTML page: <!DOCTYPE html> <html xmlns="http://www.w3.org/1999/xhtml"> <head> <title>Get Movie</title> </head> <body> <div> Title: <span id="title"></span> </div> <div> Director: <span id="director"></span> </div> <script type="text/javascript" src="Scripts/jquery-1.6.2.min.js"></script> <script type="text/javascript"> getMovie(1, function (movie) { $("#title").html(movie.Title); $("#director").html(movie.Director); }); function getMovie(id, callback) { $.ajax({ url: "/api/Movie", data: { id: id }, type: "GET", contentType: "application/json;charset=utf-8", statusCode: { 200: function (movie) { callback(movie); }, 404: function () { alert("Not Found!"); } } }); } </script> </body> </html> In the code above, the jQuery $.ajax() method is used to invoke the GetMovie() method. Notice that the Ajax call handles two HTTP response codes. When the GetMove() method successfully returns a movie, the method returns a 200 status code. In that case, the details of the movie are displayed in the HTML page. Otherwise, if the movie is not found, the GetMovie() method returns a 404 status code. In that case, the page simply displays an alert box indicating that the movie was not found (hopefully, you would implement something more graceful in an actual application). You can use your browser’s Developer Tools to see what is going on in the background when you open the HTML page (hit F12 in the most recent version of most browsers). For example, you can use the Network tab in Google Chrome to see the Ajax request which invokes the GetMovie() method: Getting a Set of Records with the ASP.NET Web API Let’s modify our Movie API controller so that it returns a collection of movies. The following Movie controller has a new ListMovies() method which returns a (hard-coded) collection of movies: using System; using System.Collections.Generic; using System.Linq; using System.Net; using System.Net.Http; using System.Web.Http; using MyWebAPIApp.Models; namespace MyWebAPIApp.Controllers { public class MovieController : ApiController { public IEnumerable<Movie> ListMovies() { return new List<Movie> { new Movie {Id=1, Title="Star Wars", Director="Lucas"}, new Movie {Id=1, Title="King Kong", Director="Jackson"}, new Movie {Id=1, Title="Memento", Director="Nolan"} }; } } } Because we named our action ListMovies(), the default Web API route will never match it. Therefore, we need to add the following custom route to our Global.asax file (at the top of the RegisterRoutes() method): routes.MapHttpRoute( name: "ActionApi", routeTemplate: "api/{controller}/{action}/{id}", defaults: new { id = RouteParameter.Optional } ); This route enables us to invoke the ListMovies() method with the URL /api/movie/listmovies. Now that we have exposed our collection of movies from the server, we can retrieve and display the list of movies using jQuery in our HTML page: <!DOCTYPE html> <html xmlns="http://www.w3.org/1999/xhtml"> <head> <title>List Movies</title> </head> <body> <div id="movies"></div> <script type="text/javascript" src="Scripts/jquery-1.6.2.min.js"></script> <script type="text/javascript"> listMovies(function (movies) { var strMovies=""; $.each(movies, function (index, movie) { strMovies += "<div>" + movie.Title + "</div>"; }); $("#movies").html(strMovies); }); function listMovies(callback) { $.ajax({ url: "/api/Movie/ListMovies", data: {}, type: "GET", contentType: "application/json;charset=utf-8", }).then(function(movies){ callback(movies); }); } </script> </body> </html>     Inserting a Record with the ASP.NET Web API Now let’s modify our Movie API controller so it supports creating new records: public HttpResponseMessage<Movie> PostMovie(Movie movieToCreate) { // Add movieToCreate to the database and update primary key movieToCreate.Id = 23; // Build a response that contains the location of the new movie var response = new HttpResponseMessage<Movie>(movieToCreate, HttpStatusCode.Created); var relativePath = "/api/movie/" + movieToCreate.Id; response.Headers.Location = new Uri(Request.RequestUri, relativePath); return response; } The PostMovie() method in the code above accepts a movieToCreate parameter. We don’t actually store the new movie anywhere. In real life, you will want to call a service method to store the new movie in a database. When you create a new resource, such as a new movie, you should return the location of the new resource. In the code above, the URL where the new movie can be retrieved is assigned to the Location header returned in the PostMovie() response. Because the name of our method starts with “Post”, we don’t need to create a custom route. The PostMovie() method can be invoked with the URL /Movie/PostMovie – just as long as the method is invoked within the context of a HTTP POST request. The following HTML page invokes the PostMovie() method. <!DOCTYPE html> <html xmlns="http://www.w3.org/1999/xhtml"> <head> <title>Create Movie</title> </head> <body> <script type="text/javascript" src="Scripts/jquery-1.6.2.min.js"></script> <script type="text/javascript"> var movieToCreate = { title: "The Hobbit", director: "Jackson" }; createMovie(movieToCreate, function (newMovie) { alert("New movie created with an Id of " + newMovie.Id); }); function createMovie(movieToCreate, callback) { $.ajax({ url: "/api/Movie", data: JSON.stringify( movieToCreate ), type: "POST", contentType: "application/json;charset=utf-8", statusCode: { 201: function (newMovie) { callback(newMovie); } } }); } </script> </body> </html> This page creates a new movie (the Hobbit) by calling the createMovie() method. The page simply displays the Id of the new movie: The HTTP Post operation is performed with the following call to the jQuery $.ajax() method: $.ajax({ url: "/api/Movie", data: JSON.stringify( movieToCreate ), type: "POST", contentType: "application/json;charset=utf-8", statusCode: { 201: function (newMovie) { callback(newMovie); } } }); Notice that the type of Ajax request is a POST request. This is required to match the PostMovie() method. Notice, furthermore, that the new movie is converted into JSON using JSON.stringify(). The JSON.stringify() method takes a JavaScript object and converts it into a JSON string. Finally, notice that success is represented with a 201 status code. The HttpStatusCode.Created value returned from the PostMovie() method returns a 201 status code. Updating a Record with the ASP.NET Web API Here’s how we can modify the Movie API controller to support updating an existing record. In this case, we need to create a PUT method to handle an HTTP PUT request: public void PutMovie(Movie movieToUpdate) { if (movieToUpdate.Id == 1) { // Update the movie in the database return; } // If you can't find the movie to update throw new HttpResponseException(HttpStatusCode.NotFound); } Unlike our PostMovie() method, the PutMovie() method does not return a result. The action either updates the database or, if the movie cannot be found, returns an HTTP Status code of 404. The following HTML page illustrates how you can invoke the PutMovie() method: <!DOCTYPE html> <html xmlns="http://www.w3.org/1999/xhtml"> <head> <title>Put Movie</title> </head> <body> <script type="text/javascript" src="Scripts/jquery-1.6.2.min.js"></script> <script type="text/javascript"> var movieToUpdate = { id: 1, title: "The Hobbit", director: "Jackson" }; updateMovie(movieToUpdate, function () { alert("Movie updated!"); }); function updateMovie(movieToUpdate, callback) { $.ajax({ url: "/api/Movie", data: JSON.stringify(movieToUpdate), type: "PUT", contentType: "application/json;charset=utf-8", statusCode: { 200: function () { callback(); }, 404: function () { alert("Movie not found!"); } } }); } </script> </body> </html> Deleting a Record with the ASP.NET Web API Here’s the code for deleting a movie: public HttpResponseMessage DeleteMovie(int id) { // Delete the movie from the database // Return status code return new HttpResponseMessage(HttpStatusCode.NoContent); } This method simply deletes the movie (well, not really, but pretend that it does) and returns a No Content status code (204). The following page illustrates how you can invoke the DeleteMovie() action: <!DOCTYPE html> <html xmlns="http://www.w3.org/1999/xhtml"> <head> <title>Delete Movie</title> </head> <body> <script type="text/javascript" src="Scripts/jquery-1.6.2.min.js"></script> <script type="text/javascript"> deleteMovie(1, function () { alert("Movie deleted!"); }); function deleteMovie(id, callback) { $.ajax({ url: "/api/Movie", data: JSON.stringify({id:id}), type: "DELETE", contentType: "application/json;charset=utf-8", statusCode: { 204: function () { callback(); } } }); } </script> </body> </html> Performing Validation How do you perform form validation when using the ASP.NET Web API? Because validation in ASP.NET MVC is driven by the Default Model Binder, and because the Web API uses the Default Model Binder, you get validation for free. Let’s modify our Movie class so it includes some of the standard validation attributes: using System.ComponentModel.DataAnnotations; namespace MyWebAPIApp.Models { public class Movie { public int Id { get; set; } [Required(ErrorMessage="Title is required!")] [StringLength(5, ErrorMessage="Title cannot be more than 5 characters!")] public string Title { get; set; } [Required(ErrorMessage="Director is required!")] public string Director { get; set; } } } In the code above, the Required validation attribute is used to make both the Title and Director properties required. The StringLength attribute is used to require the length of the movie title to be no more than 5 characters. Now let’s modify our PostMovie() action to validate a movie before adding the movie to the database: public HttpResponseMessage PostMovie(Movie movieToCreate) { // Validate movie if (!ModelState.IsValid) { var errors = new JsonArray(); foreach (var prop in ModelState.Values) { if (prop.Errors.Any()) { errors.Add(prop.Errors.First().ErrorMessage); } } return new HttpResponseMessage<JsonValue>(errors, HttpStatusCode.BadRequest); } // Add movieToCreate to the database and update primary key movieToCreate.Id = 23; // Build a response that contains the location of the new movie var response = new HttpResponseMessage<Movie>(movieToCreate, HttpStatusCode.Created); var relativePath = "/api/movie/" + movieToCreate.Id; response.Headers.Location = new Uri(Request.RequestUri, relativePath); return response; } If ModelState.IsValid has the value false then the errors in model state are copied to a new JSON array. Each property – such as the Title and Director property — can have multiple errors. In the code above, only the first error message is copied over. The JSON array is returned with a Bad Request status code (400 status code). The following HTML page illustrates how you can invoke our modified PostMovie() action and display any error messages: <!DOCTYPE html> <html xmlns="http://www.w3.org/1999/xhtml"> <head> <title>Create Movie</title> </head> <body> <script type="text/javascript" src="Scripts/jquery-1.6.2.min.js"></script> <script type="text/javascript"> var movieToCreate = { title: "The Hobbit", director: "" }; createMovie(movieToCreate, function (newMovie) { alert("New movie created with an Id of " + newMovie.Id); }, function (errors) { var strErrors = ""; $.each(errors, function(index, err) { strErrors += "*" + err + "\n"; }); alert(strErrors); } ); function createMovie(movieToCreate, success, fail) { $.ajax({ url: "/api/Movie", data: JSON.stringify(movieToCreate), type: "POST", contentType: "application/json;charset=utf-8", statusCode: { 201: function (newMovie) { success(newMovie); }, 400: function (xhr) { var errors = JSON.parse(xhr.responseText); fail(errors); } } }); } </script> </body> </html> The createMovie() function performs an Ajax request and handles either a 201 or a 400 status code from the response. If a 201 status code is returned then there were no validation errors and the new movie was created. If, on the other hand, a 400 status code is returned then there was a validation error. The validation errors are retrieved from the XmlHttpRequest responseText property. The error messages are displayed in an alert: (Please don’t use JavaScript alert dialogs to display validation errors, I just did it this way out of pure laziness) This validation code in our PostMovie() method is pretty generic. There is nothing specific about this code to the PostMovie() method. In the following video, Jon Galloway demonstrates how to create a global Validation filter which can be used with any API controller action: http://www.asp.net/web-api/overview/web-api-routing-and-actions/video-custom-validation His validation filter looks like this: using System.Json; using System.Linq; using System.Net; using System.Net.Http; using System.Web.Http.Controllers; using System.Web.Http.Filters; namespace MyWebAPIApp.Filters { public class ValidationActionFilter:ActionFilterAttribute { public override void OnActionExecuting(HttpActionContext actionContext) { var modelState = actionContext.ModelState; if (!modelState.IsValid) { dynamic errors = new JsonObject(); foreach (var key in modelState.Keys) { var state = modelState[key]; if (state.Errors.Any()) { errors[key] = state.Errors.First().ErrorMessage; } } actionContext.Response = new HttpResponseMessage<JsonValue>(errors, HttpStatusCode.BadRequest); } } } } And you can register the validation filter in the Application_Start() method in the Global.asax file like this: GlobalConfiguration.Configuration.Filters.Add(new ValidationActionFilter()); After you register the Validation filter, validation error messages are returned from any API controller action method automatically when validation fails. You don’t need to add any special logic to any of your API controller actions to take advantage of the filter. Querying using OData The OData protocol is an open protocol created by Microsoft which enables you to perform queries over the web. The official website for OData is located here: http://odata.org For example, here are some of the query options which you can use with OData: · $orderby – Enables you to retrieve results in a certain order. · $top – Enables you to retrieve a certain number of results. · $skip – Enables you to skip over a certain number of results (use with $top for paging). · $filter – Enables you to filter the results returned. The ASP.NET Web API supports a subset of the OData protocol. You can use all of the query options listed above when interacting with an API controller. The only requirement is that the API controller action returns its data as IQueryable. For example, the following Movie controller has an action named GetMovies() which returns an IQueryable of movies: public IQueryable<Movie> GetMovies() { return new List<Movie> { new Movie {Id=1, Title="Star Wars", Director="Lucas"}, new Movie {Id=2, Title="King Kong", Director="Jackson"}, new Movie {Id=3, Title="Willow", Director="Lucas"}, new Movie {Id=4, Title="Shrek", Director="Smith"}, new Movie {Id=5, Title="Memento", Director="Nolan"} }.AsQueryable(); } If you enter the following URL in your browser: /api/movie?$top=2&$orderby=Title Then you will limit the movies returned to the top 2 in order of the movie Title. You will get the following results: By using the $top option in combination with the $skip option, you can enable client-side paging. For example, you can use $top and $skip to page through thousands of products, 10 products at a time. The $filter query option is very powerful. You can use this option to filter the results from a query. Here are some examples: Return every movie directed by Lucas: /api/movie?$filter=Director eq ‘Lucas’ Return every movie which has a title which starts with ‘S’: /api/movie?$filter=startswith(Title,’S') Return every movie which has an Id greater than 2: /api/movie?$filter=Id gt 2 The complete documentation for the $filter option is located here: http://www.odata.org/developers/protocols/uri-conventions#FilterSystemQueryOption Summary The goal of this blog entry was to provide you with an overview of the new ASP.NET Web API introduced with the Beta release of ASP.NET 4. In this post, I discussed how you can retrieve, insert, update, and delete data by using jQuery with the Web API. I also discussed how you can use the standard validation attributes with the Web API. You learned how to return validation error messages to the client and display the error messages using jQuery. Finally, we briefly discussed how the ASP.NET Web API supports the OData protocol. For example, you learned how to filter records returned from an API controller action by using the $filter query option. I’m excited about the new Web API. This is a feature which I expect to use with almost every ASP.NET application which I build in the future.

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