Search Results

Search found 17771 results on 711 pages for 'mongodb query'.

Page 386/711 | < Previous Page | 382 383 384 385 386 387 388 389 390 391 392 393  | Next Page >

  • How to make a SUM of Dictionary Value nested into a list with LINQ ?

    - by user551108
    Hi All, I have a product object declared as : Product { int ProductID; string ProductName; int ProductTypeID; string ProductTypeName; int UnitsSold Dictionary <string, int> UnitsSoldByYear; } I want to make a sum on UnitsSold and UnitsSoldByYear properties with a Linq query but I didn't know how to make this kind of sum on a dictionary ! Here is my begining linq query code : var ProductTypeSum = from i in ProductsList group i by new { i.ProductTypeID, i.ProductTypeName} into pt select new { ProductTypeID= pt.Key.ProductTypeID, ProductTypeName= pt.Key.ProductTypeName, UnitsSoldSum= pt.Sum(i => i.UnitsSold), // How to make a Dictionary sum here } Thank you for your help !

    Read the article

  • SQL searching two columns for best results

    - by brsmnc
    Hi all I would like to perform an sql search and I would like to get best results. I tried some things but they didn't work well. I have got two columns named subject and content For example we will search "search this keywords" text on subject and content area. First I'm searching "search this keywords" then searching "search" and "this" and "keywords" I would like to retrieve subject's results on top and I would like to retrieve best results liking "search this keywords".My query sometimes works well sometimes not. How should I write this query Thanks..

    Read the article

  • strange behavior of <> to filter null values

    - by Kerezo
    Hi experts: I have a table Called tblAlarm and it has some records like this: I have another table for determine what user see what message: Now I want to write a query to show Messages that user has not seen if message didinot expired.(for example it's year between BeginYear and EndYear and so on ...). I write this query: SELECT * FROM tblAlarms LEFT OUTER JOIN tblUsersAlarms tua ON tblAlarms.Id=tua.MessageID WHERE @CurrentYear BETWEEN tblAlarms.BeginYear AND tblAlarms.EndYear AND @CurrentMonth BETWEEN tblAlarms.BeginMonth AND tblAlarms.EndMonth AND @CurrentDay BETWEEN tblAlarms.BeginDay AND tblAlarms.EndDay AND (@CurrentHour * 60 + @CurrentMinute) BETWEEN tblAlarms.BeginHour*60 + tblAlarms.BeginMinute AND tblAlarms.EndHour*60 + tblAlarms.EndMinute --AND (tua.UserID <> 128 AND tua.UserID IS NULL) and it returns : but if I unComment last line it does not return any record.How I can determine what messages that users has not been seen? thanks

    Read the article

  • Windows Search in Taskbar with my own results

    - by masterchris_99
    Hello, I want to provide a custom Search Connector for Windows Search without accessing a php or aspx website. Is this possible? I don't find anything. It is not possible to create tmp files because of the amount of files. I want to do a db query. Target: .net (C#) Here are 2 pics for a better explanation. What I have What I want the 3 source of information come from a external source via database query. regards Chris

    Read the article

  • What you would learn. [closed]

    - by NDeveloper
    Hi, I have a little free time and would like to learn new development language/technology. I know it can be very subective, but please share with us what you would learn and why. I have about 4 years of .NET development experience mostly distributed applications. And a little more than 2 years of c/c++. There are a lot of options to choose like Google Go/F#/Python/Scala/Java/ASP.NET/Mobile App development like for Android, BB, iPhone.../DB (MS SQL, Oracle or even MongoDB or CouchDB)/any new concepts, etc... I would like to use the time for investment, so gained knowledge will be useful.

    Read the article

  • Fetch users,logins and permissions and update the same

    - by user1490099
    Can any one please help me by giving a query or an idea which helps me? I am looking for a query which returns the users and logins in a sql server 2008 r2 instance. If some one has added/updated a user/permissions in next day- if we run a script it should revert all the changes to the previous day status. Let me give you an example On Wednesday the database security is fine On Thursday someone goes into the SQL instance and changes several database user security settings. This creates lots of problems. On Wednesday if we run a script on the SQL instance and it should reset the database user security back to what it was on Wednesday. Someone please help me in this regard, Its very urgent..............Please..........

    Read the article

  • Delete data with foreign key in SQL Server table

    - by Andha
    I'm going to delete data in an SQL Server table (parent) which has a relationship with another table (child). I tried the basic Delete query. But it isn't working (and I know it won't). DELETE FROM table WHERE ... It returned following error The DELETE statement conflicted with the REFERENCE constraint ... I need to keep the table's schema. I know that I just need to add some words in the query, I've ever done this before, but I just couldn't recall it.

    Read the article

  • Mysql slowing down my application

    - by user2985991
    my application is taking ages to load because of my database isnt located on my computer.. Anyone have any idea to how improve my performance? public Form1() { Splash splash = new Splash(); splash.Show(); InitializeComponent(); Load(); public void Load() { db.SelectTeam(); db.SelectMatches(); } On db.SelectTeam and SelectMatches I get everything I need from mysql and put into lists... Sorry if it's confusing, but I don't know what to do, and sorry for my bad english EDIT: Here are the querys string query = "SELECT * FROM teams ORDER BY name"; string query = "SELECT * FROM matches ORDER BY date ASC";

    Read the article

  • MYSQL accentuated characters é display as %E9

    - by Jk_
    Hi guys, I'm pushing data from as3 to MSQL through a little php script! My problem is that all my accentuated characters are displayed as weird iso characters. Example : é is displayed %E9 Obvisously the collation of my field is set to utf8_general_ci Even when I try to INSERT the data from a simple php script without as3, I get the same mistake. <?php mysql_connect("***", "***", "***") or die("Error :" .mysql_error()); mysql_select_db("***"); $query ="INSERT INTO test (message) values ('éèàïû')"; mysql_query($query) or die("Error updating DB"); ?> Any idea on what am I doing wrong and how I could fix that? Thanks in advance. Jk_

    Read the article

  • Why does Cacti keep waiting for dead poller processes?

    - by Oliver Salzburg
    sorry for the length I am currently setting up a new Debian (6.0.5) server. I put Cacti (0.8.7g) on it yesterday and have been battling with it ever since. Initial issue The initial issue I was observing, was that my graphs weren't updating. So I checked my cacti.log and found this concerning message: POLLER: Poller[0] Maximum runtime of 298 seconds exceeded. Exiting. That can't be good, right? So I went checking and started poller.php myself (via sudo -u www-data php poller.php --force). It will pump out a lot of message (which all look like what I would expect) and then hang for a minute. After that 1 minute, it will loop the following message: Waiting on 1 of 1 pollers. This goes on for 4 more minutes until the process is forcefully ended for running longer than 300s. So far so good I went on for a good hour trying to determine what poller might still be running, until I got to the conclusion that there simply is no running poller. Debugging I checked poller.php to see how that warning is issued and why. On line 368, Cacti will retrieve the number of finished processes from the database and use that value to calculate how many processes are still running. So, let's see that value! I added the following debug code into poller.php: print "Finished: " . $finished_processes . " - Started: " . $started_processes . "\n"; Result This will print the following within seconds of starting poller.php: Finished: 0 - Started: 1 Waiting on 1 of 1 pollers. Finished: 1 - Started: 1 So the values are being read and are valid. Until we get to the part where it keeps looping: Finished: - Started: 1 Waiting on 1 of 1 pollers. Suddenly, the value is gone. Why? Putting var_dump() in there confirms the issue: NULL Finished: - Started: 1 Waiting on 1 of 1 pollers. The return value is NULL. How can that be when querying SELECT COUNT()...? (SELECT COUNT() should always return one result row, shouldn't it?) More debugging So I went into lib\database.php and had a look at that db_fetch_cell(). A bit of testing confirmed, that the result set is actually empty. So I added my own database query code in there to see what that would do: $finished_processes = db_fetch_cell("SELECT count(*) FROM poller_time WHERE poller_id=0 AND end_time>'0000-00-00 00:00:00'"); print "Finished: " . $finished_processes . " - Started: " . $started_processes . "\n"; $mysqli = new mysqli("localhost","cacti","cacti","cacti"); $result = $mysqli->query("SELECT COUNT(*) FROM poller_time WHERE poller_id=0 AND end_time>'0000-00-00 00:00:00';"); $row = $result->fetch_assoc(); var_dump( $row ); This will output Finished: - Started: 1 array(1) { ["COUNT(*)"]=> string(1) "2" } Waiting on 1 of 1 pollers. So, the data is there and can be accessed without any problems, just not with the method Cacti is using? Double-check that! I enabled MySQL logging to make sure I'm not imagining things. Sure enough, when the error message is looped, the cacti.log reads as if it was querying like mad: 06/29/2012 08:44:00 PM - CMDPHP: Poller[0] DEVEL: SQL Cell: "SELECT count(*) FROM cacti.poller_time WHERE poller_id=0 AND end_time>'0000-00-00 00:00:00'" 06/29/2012 08:44:01 PM - CMDPHP: Poller[0] DEVEL: SQL Cell: "SELECT count(*) FROM cacti.poller_time WHERE poller_id=0 AND end_time>'0000-00-00 00:00:00'" 06/29/2012 08:44:02 PM - CMDPHP: Poller[0] DEVEL: SQL Cell: "SELECT count(*) FROM cacti.poller_time WHERE poller_id=0 AND end_time>'0000-00-00 00:00:00'" But none of these queries are logged my MySQL. Yet, when I add my own database query code, it shows up just fine. What the heck is going on here?

    Read the article

  • Wget works, Ping doesn't

    - by derty
    There are some anomalies on a Virtuozzo virtualized Debian 4 (I know, I'm gonna upgrade this one asap, but there dependences). We run some Websites on this one. And a view Days ago exmi4 wasnt able to send mails to SOME people. I'll use live.com as exampledomain! So some of this people got mails and some didn't. Some of the mails got stuck in the queue, and after 2 days they went out!! My Nagios never showed problems with the internet connection or disk space Now i wanted to install "dig" to look how he's solving the dns request. And this Debian tells me he doesn't know dig.. Long story made short, Debian is able to download sites with exact IP or even with wget live.com, but it is not able to ping live.com. I'm 99% sure that the networking is right and the routing too! Some examples of my tring below: wget live.com downloads the site ping live.com ping http://www.live.com ping http://live.com returns: ping: unknown host live.com EDIT: i now use heise.de not live.com any more. and i found out i can ping the heise.de server by using it's IP-address. myserver:~# ping 193.99.144.85 PING 193.99.144.85 (193.99.144.85) 56(84) bytes of data. 64 bytes from 193.99.144.85: icmp_seq=1 ttl=248 time=12.7 ms 64 bytes from 193.99.144.85: icmp_seq=2 ttl=248 time=12.6 ms 64 bytes from 193.99.144.85: icmp_seq=3 ttl=248 time=12.9 ms 64 bytes from 193.99.144.85: icmp_seq=4 ttl=248 time=13.1 ms 64 bytes from 193.99.144.85: icmp_seq=5 ttl=248 time=13.1 ms --- 193.99.144.85 ping statistics --- 5 packets transmitted, 5 received, 0% packet loss, time 4001ms rtt min/avg/max/mdev = 12.671/12.924/13.163/0.238 ms EDIT 2: myserver:/etc/apt# dig heise.de ; <<>> DiG 9.3.4-P1.2 <<>> heise.de ;; global options: printcmd ;; Got answer: ;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 40551 ;; flags: qr rd ra; QUERY: 1, ANSWER: 1, AUTHORITY: 5, ADDITIONAL: 3 ;; QUESTION SECTION: ;heise.de. IN A ;; ANSWER SECTION: heise.de. 2266 IN A 193.99.144.80 ;; AUTHORITY SECTION: heise.de. 1622 IN NS ns.pop-hannover.de. heise.de. 1622 IN NS ns.s.plusline.de. heise.de. 1622 IN NS ns.plusline.de. heise.de. 1622 IN NS ns2.pop-hannover.net. heise.de. 1622 IN NS ns.heise.de. ;; ADDITIONAL SECTION: ns.plusline.de. 265 IN A 212.19.48.14 ns.pop-hannover.de. 5113 IN A 193.98.1.200 ns2.pop-hannover.net. 15150 IN A 62.48.67.66 ;; Query time: 2 msec ;; SERVER: 193.200.112.80#53(193.200.112.80) ;; WHEN: Tue Oct 9 13:03:50 2012 ;; MSG SIZE rcvd: 216

    Read the article

  • Extended URL php

    - by web.ask
    I have a problem with the extended url here in php. I'm not even sure if it's called extended url. I was wondering if someone can help me since i'm no good with PHP. I have a php page the careers.php it shows the career listing but when I click on Learn more link it goes to http(dot)localhost/houseofpatel/jobs/4/Career-4 but it outputs an "Object not found". Does xampplite have something to do with this? or is it just the codes? I also have the breadcrumb.php in here. Please see code below: session_start(); include("Breadcrumb.php"); $trail = new Breadcrumb(); $trail->add('Careers', $_SERVER['PHP_SELF'], 1); $trail -> output(); # REMOVE SPECIAL CHARACTERS $sPattern = array('/[^a-zA-Z0-9 -]/', '/[ -]+/', '/^-|-$/'); $sReplace = array('', '-', ''); mysql_query("SET CHARACTER_SET utf8"); //$query = "SELECT * FROM careers_mst WHERE status = 1 ORDER BY dateposted DESC LIMIT 0, 4"; if(!$_GET['jobs']){ $jobsPerPage = 4; }else{ $jobsPerPage = $_GET['jobs']; } if(!$_GET['page']){ $currPage = 1; $showMoreJobs = true; }else{ $currPage = $_GET['page']; $showMoreJobs = false; } $offset = ($currPage - 1 )* $jobsPerPage; $query = "SELECT * FROM careers_mst WHERE status = 1 ORDER BY dateposted"; $process = mysql_query($query); if(@mysql_num_rows($process) > 0){ $totalRows = @mysql_num_rows($process); $query2 = "SELECT * FROM careers_mst WHERE status = 1 ORDER BY dateposted DESC LIMIT $offset, $jobsPerPage"; $process2 = mysql_query($query2); if(@mysql_num_rows($process2) > 0){ $pagNav = pageNavigator($totalRows,$jobsPerPage,$currPage,''); while($row = @mysql_fetch_array($process2)){ $id = $row[0]; $title = stripslashes($row['title']); $title1 = preg_replace($sPattern, $sReplace, $title); $description = stripslashes($row['description']); $description1 = substr($description, 0, 200); $careers_list .= ' <div class="left" style="width:340px; padding-left:10px;"> <p><span class="blue"><strong>'.$title.'</strong></span></p> '.$description1.'... <p><a href="jobs/'.$id.'/'.$title1.'" title="Learn more">[ Learn More ]</a></p> </div>'; } /*$careers_list .= ' <div class="left" style="width: 100%; margin-top:15px;"> <p><a href="more-jobs" title="More Job Opennings">MORE JOB OPENNINGS >> </a></p> <div class="divider left"></div> </div>'; */ if($showMoreJobs){ if($totalRows > $jobsPerPage){ $currPage++; } $jobNav = "<a href=careers.php?page=$currPage title='More Job Opennings'>MORE JOB OPENNINGS >> </a>"; }else{ $jobNav = "$pagNav"; } $careers_list .= "<div class='left' style='width: 100%; margin-top:15px;'> <p>$jobNav</p> <div class='divider left'></div> </div>"; } }

    Read the article

  • Connection Timed Out - Simple outbound Postfix for PHP Contact form

    - by BLaZuRE
    Alright, so I only got Postfix for a PHP contact form that will send email to a single . I only want it to send out mail to a single external address ([email protected]). I have domain sub1.sub2.domain.com. I installed Postfix out of the Ubuntu repo, with minimal config changes. I cannot get Postfix to send mail externally (though it succeeds for internal accounts, which is unnecessary). The email simply defers if I generate an email using PHP mail(). If I try to form my own in telnet, right after rcpt to: [email][email protected][/email], I get a postfix/smtpd[31606]: NOQUEUE: reject: RCPT from localhost[127.0.0.1]: 550 5.1.1 <[email protected]>: Recipient address rejected: example.com; from=<root@localhost> to=<[email protected]> proto=ESMTP helo=<localhost> when commenting out default_transport = error and relay_transport = error lines, I get the following: Jun 26 14:33:00 sub1 postfix/smtp[12191]: 2DA06F88206A: to=<[email protected]>, relay=none, delay=514, delays=409/0.01/105/0, dsn=4.4.1, status=deferred (connect to aspmx3.googlemail.com[74.125.127.27]:25: Connection timed out) Jun 26 14:36:36 sub1 postfix/smtp[12225]: connect to mta7.am0.yahoodns.net[98.139.175.224]:25: Connection timed out Jun 26 14:38:00 sub1 postfix/smtp[12225]: 22952F88208E: to=<[email protected]>, relay=none, delay=655, delays=550/0.01/105/0, dsn=4.4.1, status=deferred (connect to mta5.am0.yahoodns.net[67.195.168.230]:25: Connection timed out) My main.cf # See /usr/share/postfix/main.cf.dist for a commented, more complete version # Debian specific: Specifying a file name will cause the first # line of that file to be used as the name. The Debian default # is /etc/mailname. #myorigin = /etc/mailname smtpd_banner = $myhostname ESMTP $mail_name (Ubuntu) biff = no # appending .domain is the MUA's job. append_dot_mydomain = no # Uncomment the next line to generate "delayed mail" warnings #delay_warning_time = 4h readme_directory = no # TLS parameters smtpd_tls_cert_file=/etc/ssl/certs/ssl-cert-snakeoil.pem smtpd_tls_key_file=/etc/ssl/private/ssl-cert-snakeoil.key smtpd_use_tls=yes smtpd_tls_session_cache_database = btree:${data_directory}/smtpd_scache smtp_tls_session_cache_database = btree:${data_directory}/smtp_scache # See /usr/share/doc/postfix/TLS_README.gz in the postfix-doc package for # information on enabling SSL in the smtp client. myhostname = sub1.sub2.domain.com alias_maps = hash:/etc/aliases alias_database = hash:/etc/aliases myorigin = /etc/mailname mydestination = sub1.sub2.domain.com, localhost relayhost = mynetworks = 127.0.0.0/8 [::ffff:127.0.0.0]/104 [::1]/128 mailbox_size_limit = 0 recipient_delimiter = + inet_interfaces = all default_transport = error relay_transport = error Also, a dig sub1.sub2.domain.com MX returns: ; <<>> DiG 9.7.0-P1 <<>> sub1.sub2.domain.com MX ;; global options: +cmd ;; Got answer: ;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 4853 ;; flags: qr aa rd ra; QUERY: 1, ANSWER: 0, AUTHORITY: 1, ADDITIONAL: 0 ;; QUESTION SECTION: ;sub1.sub2.domain.com. IN MX ;; AUTHORITY SECTION: sub2.domain.com. 600 IN SOA sub2.domain.com. sub5.domain.com. 2012062915 7200 600 1209600 600 ;; Query time: 0 msec ;; SERVER: x.x.x.x#53(x.x.x.x) ;; WHEN: Fri Jun 29 16:35:00 2012 ;; MSG SIZE rcvd: 84 lsof -i returns empty netstat -t -a | grep LISTEN returns tcp 0 0 localhost:mysql *:* LISTEN tcp 0 0 *:ftp *:* LISTEN tcp 0 0 *:ssh *:* LISTEN tcp 0 0 localhost:ipp *:* LISTEN tcp 0 0 *:smtp *:* LISTEN tcp6 0 0 [::]:netbios-ssn [::]:* LISTEN tcp6 0 0 [::]:www [::]:* LISTEN tcp6 0 0 [::]:ssh [::]:* LISTEN tcp6 0 0 localhost:ipp [::]:* LISTEN tcp6 0 0 [::]:microsoft-ds [::]:* LISTEN

    Read the article

  • Bypass DNSSEC for local Stub zones

    - by Starsky
    I am using bind 9.9.2 as a DNSSEC validating recursive resolver in an Internet DMZ. I want to point to my internal DNS servers as stub zones (ideally) or anything except slave zones (to avoid very large zone transfers). We use a routable ip space for our Internal addressing. Sorry if I am using an IP space that you own in my example, but 167.x.x.x is the first zone I found that fits my issue. E.G dnssec-enable yes; dnssec-validation yes; dnssec-accept-expired no; zone "16.172.in-addr.arpa" { type stub; masters { 167.255.1.53; } } zone "myzone.com" in { type stub; masters { 167.255.1.53; } } When queries hit the DNS server, they attempt at being validated, and fail because 167.in-addr.arpa HAS an RRSIG record, but sub zones do not (and should not!). Google dns is used in this example, but in reality it would be my recursive resolver. @8.8.8.8 -x 167.255.1.53 +dnssec ; (1 server found) ;; global options: +cmd ;; Got answer: ;; ->>HEADER<<- opcode: QUERY, status: NXDOMAIN, id: 17488 ;; flags: qr rd ra ad; QUERY: 1, ANSWER: 0, AUTHORITY: 6, ADDITIONAL: 1 ;; OPT PSEUDOSECTION: ; EDNS: version: 0, flags: do; udp: 512 ;; QUESTION SECTION: ;53.1.255.167.in-addr.arpa. IN PTR ;; AUTHORITY SECTION: 167.in-addr.arpa. 1800 IN SOA z.arin.net. dns-ops.arin.net. 2013100713 1800 900 691200 10800 167.in-addr.arpa. 1800 IN RRSIG SOA 5 3 86400 20131017160124 20131007160124 812 167.in-addr.arpa. Lcl8sCps7LapnAj4n403KXx7A3GO7+2z/9Q2R2mwkh9FL26iDx7GlU4+ NufGd92IEJCdBu9IgcZP4I9QcKi8DI28og27WrfKd5moSl/STj02GliS qPTfNiewmTTIDw5++IlhITbp+CoJuZCRCdDbyWKmd5NSLcbskAwbCVlO vVA= 167.in-addr.arpa. 10800 IN NSEC 1.167.in-addr.arpa. NS SOA TXT RRSIG NSEC DNSKEY 167.in-addr.arpa. 10800 IN RRSIG NSEC 5 3 10800 20131017160124 20131007160124 812 167.in-addr.arpa. XALsd59i+XGvCIzjhTUFXcr11/M8prcaaPQ5yFSbvP9TzqjJ3wpizvH6 202MdrIWbsT1Dndri49lHKAXgBQ5OOsUmOh+eoRYR5okxRO4VLc5Tkze Gh0fQLcwGXPuv9A4SFNIrNyi3XU4Qvq0cViKXIuEGTa3C+zMPuvc0her oKk= 254.167.in-addr.arpa. 10800 IN NSEC 26.167.in-addr.arpa. NS RRSIG NSEC 254.167.in-addr.arpa. 10800 IN RRSIG NSEC 5 4 10800 20131017160124 20131007160124 812 167.in-addr.arpa. xnsLBTnPhdyABdvqtEHPxa6Y6NASfYAWfW1yYlNliTyV8TFeNOqewjwj nY43CWD77ftFDDQTLFEOPpV5vwmnUGYTRztK+kB5UrlflhPgiqYiBaBD RQaFQ8DIKaof8/snusZjK7aNmfe09t9gRcaX/pXn3liKz7m/ggxZi0f9 xo0= ;; Query time: 31 msec ;; SERVER: 8.8.8.8#53(8.8.8.8) ;; WHEN: Mon Oct 7 16:52:59 2013 ;; MSG SIZE rcvd: 722 Is there a way to bypass DNSSEC validation for specific zones? Any zone that I host internally, I do not want DNSSEC validation performed on. I have only see this interfere w/ certain reverse zones where the top level has DS/RRSIG records. Thanks.

    Read the article

  • CPU Utilization LAMP stack

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

    Read the article

  • AWS Load balancer connection reset

    - by joshmmo
    I have an ELB set up with two instances. The issue I have with it is that when I do not add www. to it, the ELB just hangs. This is some info I get when I spider with wget: Spider mode enabled. Check if remote file exists. --2013-06-20 13:40:54-- http://learning.example.com/ Resolving learning.example.com... 54.xxx.x.x53, 50.xx.xxx.x71 Connecting to learning.example.com|54.xxx.x.x53|:80... connected. HTTP request sent, awaiting response... No data received. Retrying. when I add www. it works great. I have a GoDaddy SSL cert that I added to the listener section that covers 3 domains, www.learning.example.com, files.learning.example.com and learning.example.com. These are my listener settings: - HTTP 80 HTTPS 443 N/A N/A - SSL 443 SSL 443 Change canvasNew (Change) My EC2 instances are running apache2 on Ubuntu 12.04. I will be happy to post my vhosts file if needed. However, when I ran the server with the domains pointing to just one EC2 instance things worked fine. How can I fix this issue for learning.example.com? Why does www work just fine? A second question would be what is the difference between instance protocol and load balancer protocol? EDIT: Here are the dig results for learning.example.com from yesterday. I changed the DNS entry to point to one instance to make sure it was the elb. When I switch it back I will do it for www.learning.example.com ; <<>> DiG 9.9.1-P2 <<>> learning.example.com ;; global options: +cmd ;; Got answer: ;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 20210 ;; flags: qr rd ra; QUERY: 1, ANSWER: 3, AUTHORITY: 0, ADDITIONAL: 0 ;; QUESTION SECTION: ;learning.example.com. IN A ;; ANSWER SECTION: learning.example.com. 2559 IN CNAME canvas-22222222222.us-west-1.elb.amazonaws.com. canvas-22222222222.us-west-1.elb.amazonaws.com. 60 IN A 54.xxx.x.x53 canvas-22222222222.us-west-1.elb.amazonaws.com. 60 IN A 50.xx.xxx.x71 ;; Query time: 83 msec ;; SERVER: 10.x.xx.20#53(10.x.xx.20) ;; WHEN: Thu Jun 20 13:40:47 2013 ;; MSG SIZE rcvd: 137 EDIT 2: Here is some more info that might be helpful. Port Configuration: 80 (HTTP) forwarding to 443 (HTTPS) Backend Authentication: Disabled Stickiness: Disabled(edit) 443 (SSL, Certificate: canvasNew) forwarding to 443 (SSL) Backend Authentication: Disabled So I switched everything to one EC2 IP address to bypass the elb to make sure things are working. It's running great. www and the non-www url work perfectly fine. Its only when I switch things to the ELB that learning.example.com hangs and www.learning.example.com works. Hopefully you can get some ideas flowing.

    Read the article

  • MySQL reserves too much RAM

    - by Buddy
    I have a cheap VPS with 128Mb RAM and 256Mb burst. MySQL starts and reserves about 110Mb, but uses not more than 20Mb of them. My VPS Control Panel shows, that I use 127Mb (I also running nginx and sphinx), I know, that it shows reserved RAM, but when I reach over 128Mb, my VPS reboots automatically every 4 hours. So I want to force MySQL to reserve less RAM. How can i do that? I did some tweaks with my.conf but it helped not so much. top output: PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND 1 root 15 0 2156 668 572 S 0.0 0.3 0:00.03 init 11311 root 15 0 11212 356 228 S 0.0 0.1 0:00.00 vzctl 11312 root 18 0 3712 1484 1248 S 0.0 0.6 0:00.01 bash 11347 root 18 0 2284 916 732 R 0.0 0.3 0:00.00 top 13978 root 17 -4 2248 552 344 S 0.0 0.2 0:00.00 udevd 14262 root 15 0 1812 564 472 S 0.0 0.2 0:00.03 syslogd 14293 sphinx 15 0 11816 1172 672 S 0.0 0.4 0:00.07 searchd 14305 root 25 0 7192 1036 636 S 0.0 0.4 0:00.00 sshd 14321 root 25 0 2832 836 668 S 0.0 0.3 0:00.00 xinetd 15389 root 18 0 3708 1300 1132 S 0.0 0.5 0:00.00 mysqld_safe 15441 mysql 15 0 113m 16m 4440 S 0.0 6.4 0:00.15 mysqld 15489 root 21 0 13056 1456 340 S 0.0 0.6 0:00.00 nginx 15490 nginx 18 0 13328 2388 992 S 0.0 0.9 0:00.06 nginx 15507 nginx 25 0 19520 5888 4244 S 0.0 2.2 0:00.00 php-cgi 15508 nginx 18 0 19636 4876 2748 S 0.0 1.9 0:00.12 php-cgi 15509 nginx 15 0 19668 4872 2716 S 0.0 1.9 0:00.11 php-cgi 15518 root 18 0 4492 1116 568 S 0.0 0.4 0:00.01 crond MySQL tuner: >> MySQLTuner 1.0.1 - Major Hayden <[email protected]> >> Bug reports, feature requests, and downloads at http://mysqltuner.com/ >> Run with '--help' for additional options and output filtering Please enter your MySQL administrative login: root Please enter your MySQL administrative password: -------- General Statistics -------------------------------------------------- [--] Skipped version check for MySQLTuner script [OK] Currently running supported MySQL version 5.0.77 [OK] Operating on 32-bit architecture with less than 2GB RAM -------- Storage Engine Statistics ------------------------------------------- [--] Status: -Archive -BDB -Federated +InnoDB -ISAM -NDBCluster [--] Data in InnoDB tables: 1M (Tables: 1) [OK] Total fragmented tables: 0 -------- Performance Metrics ------------------------------------------------- [--] Up for: 38m 43s (37 q [0.016 qps], 20 conn, TX: 4M, RX: 3K) [--] Reads / Writes: 100% / 0% [--] Total buffers: 28.1M global + 832.0K per thread (100 max threads) [OK] Maximum possible memory usage: 109.4M (42% of installed RAM) [OK] Slow queries: 0% (0/37) [OK] Highest usage of available connections: 1% (1/100) [OK] Key buffer size / total MyISAM indexes: 128.0K/64.0K [OK] Query cache efficiency: 42.1% (8 cached / 19 selects) [OK] Query cache prunes per day: 0 [!!] Temporary tables created on disk: 27% (3 on disk / 11 total) [!!] Thread cache is disabled [OK] Table cache hit rate: 57% (8 open / 14 opened) [OK] Open file limit used: 1% (12/1K) [OK] Table locks acquired immediately: 100% (22 immediate / 22 locks) [!!] Connections aborted: 10% [OK] InnoDB data size / buffer pool: 1.5M/8.0M -------- Recommendations ----------------------------------------------------- General recommendations: MySQL started within last 24 hours - recommendations may be inaccurate Enable the slow query log to troubleshoot bad queries When making adjustments, make tmp_table_size/max_heap_table_size equal Reduce your SELECT DISTINCT queries without LIMIT clauses Set thread_cache_size to 4 as a starting value Your applications are not closing MySQL connections properly Variables to adjust: tmp_table_size (> 32M) max_heap_table_size (> 16M) thread_cache_size (start at 4) I think if I do what MySQLtuner says, MySQL will use more RAM.

    Read the article

  • NoSQL with RavenDB and ASP.NET MVC - Part 1

    - by shiju
     A while back, I have blogged NoSQL with MongoDB, NoRM and ASP.NET MVC Part 1 and Part 2 on how to use MongoDB with an ASP.NET MVC application. The NoSQL movement is getting big attention and RavenDB is the latest addition to the NoSQL and document database world. RavenDB is an Open Source (with a commercial option) document database for the .NET/Windows platform developed  by Ayende Rahien.  Raven stores schema-less JSON documents, allow you to define indexes using Linq queries and focus on low latency and high performance. RavenDB is .NET focused document database which comes with a fully functional .NET client API  and supports LINQ. RavenDB comes with two components, a server and a client API. RavenDB is a REST based system, so you can write your own HTTP cleint API. As a .NET developer, RavenDB is becoming my favorite document database. Unlike other document databases, RavenDB is supports transactions using System.Transactions. Also it's supports both embedded and server mode of database. You can access RavenDB site at http://ravendb.netA demo App with ASP.NET MVCLet's create a simple demo app with RavenDB and ASP.NET MVC. To work with RavenDB, do the following steps. Go to http://ravendb.net/download and download the latest build.Unzip the downloaded file.Go to the /Server directory and run the RavenDB.exe. This will start the RavenDB server listening on localhost:8080You can change the port of RavenDB  by modifying the "Raven/Port" appSetting value in the RavenDB.exe.config file.When running the RavenDB, it will automatically create a database in the /Data directory. You can change the directory name data by modifying "Raven/DataDirt" appSetting value in the RavenDB.exe.config file.RavenDB provides a browser based admin tool. When the Raven server is running, You can be access the browser based admin tool and view and edit documents and index using your browser admin tool. The web admin tool available at http://localhost:8080The below is the some screen shots of web admin tool     Working with ASP.NET MVC  To working with RavenDB in our demo ASP.NET MVC application, do the following steps Step 1 - Add reference to Raven Cleint API In our ASP.NET MVC application, Add a reference to the Raven.Client.Lightweight.dll from the Client directory. Step 2 - Create DocumentStoreThe document store would be created once per application. Let's create a DocumentStore on application start-up in the Global.asax.cs. documentStore = new DocumentStore { Url = "http://localhost:8080/" }; documentStore.Initialise(); The above code will create a Raven DB document store and will be listening the server locahost at port 8080    Step 3 - Create DocumentSession on BeginRequest   Let's create a DocumentSession on BeginRequest event in the Global.asax.cs. We are using the document session for every unit of work. In our demo app, every HTTP request would be a single Unit of Work (UoW). BeginRequest += (sender, args) =>   HttpContext.Current.Items[RavenSessionKey] = documentStore.OpenSession(); Step 4 - Destroy the DocumentSession on EndRequest  EndRequest += (o, eventArgs) => {     var disposable = HttpContext.Current.Items[RavenSessionKey] as IDisposable;     if (disposable != null)         disposable.Dispose(); };  At the end of HTTP request, we are destroying the DocumentSession  object.The below  code block shown all the code in the Global.asax.cs  private const string RavenSessionKey = "RavenMVC.Session"; private static DocumentStore documentStore;   protected void Application_Start() { //Create a DocumentStore in Application_Start //DocumentStore should be created once per application and stored as a singleton. documentStore = new DocumentStore { Url = "http://localhost:8080/" }; documentStore.Initialise(); AreaRegistration.RegisterAllAreas(); RegisterRoutes(RouteTable.Routes); //DI using Unity 2.0 ConfigureUnity(); }   public MvcApplication() { //Create a DocumentSession on BeginRequest   //create a document session for every unit of work BeginRequest += (sender, args) =>     HttpContext.Current.Items[RavenSessionKey] = documentStore.OpenSession(); //Destroy the DocumentSession on EndRequest EndRequest += (o, eventArgs) => { var disposable = HttpContext.Current.Items[RavenSessionKey] as IDisposable; if (disposable != null) disposable.Dispose(); }; }   //Getting the current DocumentSession public static IDocumentSession CurrentSession {   get { return (IDocumentSession)HttpContext.Current.Items[RavenSessionKey]; } }  We have setup all necessary code in the Global.asax.cs for working with RavenDB. For our demo app, Let’s write a domain class  public class Category {       public string Id { get; set; }       [Required(ErrorMessage = "Name Required")]     [StringLength(25, ErrorMessage = "Must be less than 25 characters")]     public string Name { get; set;}     public string Description { get; set; }   } We have created simple domain entity Category. Let's create repository class for performing CRUD operations against our domain entity Category.  public interface ICategoryRepository {     Category Load(string id);     IEnumerable<Category> GetCategories();     void Save(Category category);     void Delete(string id);       }    public class CategoryRepository : ICategoryRepository {     private IDocumentSession session;     public CategoryRepository()     {             session = MvcApplication.CurrentSession;     }     //Load category based on Id     public Category Load(string id)     {         return session.Load<Category>(id);     }     //Get all categories     public IEnumerable<Category> GetCategories()     {         var categories= session.LuceneQuery<Category>()                 .WaitForNonStaleResults()             .ToArray();         return categories;       }     //Insert/Update category     public void Save(Category category)     {         if (string.IsNullOrEmpty(category.Id))         {             //insert new record             session.Store(category);         }         else         {             //edit record             var categoryToEdit = Load(category.Id);             categoryToEdit.Name = category.Name;             categoryToEdit.Description = category.Description;         }         //save the document session         session.SaveChanges();     }     //delete a category     public void Delete(string id)     {         var category = Load(id);         session.Delete<Category>(category);         session.SaveChanges();     }        } For every CRUD operations, we are taking the current document session object from HttpContext object. session = MvcApplication.CurrentSession; We are calling the static method CurrentSession from the Global.asax.cs public static IDocumentSession CurrentSession {     get { return (IDocumentSession)HttpContext.Current.Items[RavenSessionKey]; } }  Retrieve Entities  The Load method get the single Category object based on the Id. RavenDB is working based on the REST principles and the Id would be like categories/1. The Id would be created by automatically when a new object is inserted to the document store. The REST uri categories/1 represents a single category object with Id representation of 1.   public Category Load(string id) {    return session.Load<Category>(id); } The GetCategories method returns all the categories calling the session.LuceneQuery method. RavenDB is using a lucen query syntax for querying. I will explain more details about querying and indexing in my future posts.   public IEnumerable<Category> GetCategories() {     var categories= session.LuceneQuery<Category>()             .WaitForNonStaleResults()         .ToArray();     return categories;   } Insert/Update entityFor insert/Update a Category entity, we have created Save method in repository class. If  the Id property of Category is null, we call Store method of Documentsession for insert a new record. For editing a existing record, we load the Category object and assign the values to the loaded Category object. The session.SaveChanges() will save the changes to document store.  //Insert/Update category public void Save(Category category) {     if (string.IsNullOrEmpty(category.Id))     {         //insert new record         session.Store(category);     }     else     {         //edit record         var categoryToEdit = Load(category.Id);         categoryToEdit.Name = category.Name;         categoryToEdit.Description = category.Description;     }     //save the document session     session.SaveChanges(); }  Delete Entity  In the Delete method, we call the document session's delete method and call the SaveChanges method to reflect changes in the document store.  public void Delete(string id) {     var category = Load(id);     session.Delete<Category>(category);     session.SaveChanges(); }  Let’s create ASP.NET MVC controller and controller actions for handling CRUD operations for the domain class Category  public class CategoryController : Controller { private ICategoryRepository categoyRepository; //DI enabled constructor public CategoryController(ICategoryRepository categoyRepository) {     this.categoyRepository = categoyRepository; } public ActionResult Index() {         var categories = categoyRepository.GetCategories();     if (categories == null)         return RedirectToAction("Create");     return View(categories); }   [HttpGet] public ActionResult Edit(string id) {     var category = categoyRepository.Load(id);         return View("Save",category); } // GET: /Category/Create [HttpGet] public ActionResult Create() {     var category = new Category();     return View("Save", category); } [HttpPost] public ActionResult Save(Category category) {     if (!ModelState.IsValid)     {         return View("Save", category);     }           categoyRepository.Save(category);         return RedirectToAction("Index");     }        [HttpPost] public ActionResult Delete(string id) {     categoyRepository.Delete(id);     var categories = categoyRepository.GetCategories();     return PartialView("CategoryList", categories);      }        }  RavenDB is an awesome document database and I hope that it will be the winner in .NET space of document database world.  The source code of demo application available at http://ravenmvc.codeplex.com/

    Read the article

  • SQL Server Editions and Integration Services

    The SQL Server 2005 and SQL Server 2008 product family has quite a few editions now, so what does this mean for SQL Server Integration Services? Starting from the bottom we have the free edition known as Express, and the entry level Workgroup edition, as well as the new Web edition. None of these three include the full SSIS product, but they do all include the SQL Server Import and Export Wizard, with access to basic data sources but nothing more, so for simple loading and extraction of data this should suffice. You will not be able to build packages though, this is just a one shot deal aimed at using the wizard on an ad-hoc basis. To get the full power of Integration Services you need to start with Standard edition. This includes the BI Development Studio, for building your own packages, and fully functional IDE integrated into Visual Studio. (You get the full VS 2005/2008 IDE with the product). All core functions will be available but with a restricted set of transformations and tasks. The SQL Server 2005 Features Comparison or Features Supported by the Editions of SQL Server 2008 describes standard edition as having basic transforms, compared to Enterprise which includes the advanced transforms. I think basic is a little harsh considering the power you get with Standard, but the advanced covers the truly ground-breaking capabilities of data mining, text mining and cleansing or fuzzy transforms. The power of performing these operations within your ETL pipeline should not be underestimated, but not all processes will require these capabilities, so it seems like a reasonable delineation. Thankfully there are no feature limitations or artificial governors within Standard compared to Enterprise. The same control flow and data flow engines underpin both editions, with the same configuration and deployment options allowing you to work seamlessly between environments and editions if using the common components. In fact there are no govenors at all in SSIS, so whilst the SQL Database engine is limited to 4 CPUs in Standard edition, SSIS is only limited by the base operating system. The advanced transforms only available with Enterprise edition: Data Mining Training Destination Data Mining Query Component Fuzzy Grouping Fuzzy Lookup Term Extraction Term Lookup Dimension Processing Destination Partition Processing Destination The advanced tasks only available with Enterprise edition: Data Mining Query Task So in summary, if you want SQL Server Integration Services, you need SQL Server Standard edition, and for the more advanced tasks and transforms you need SQL Server Enterprise edition. To recap, the answer to the often asked question is no, SQL Server Integration Services is not available in SQL Server Express or Workgroup editions.

    Read the article

  • Top 10 Reasons SQL Developer is Perfect for Oracle Beginners

    - by thatjeffsmith
    Learning new technologies can be daunting. If you’ve never used a Mac before, you’ll probably be a bit baffled at first. But, you’re probably at least coming from a desktop computing background (Windows), so you common frame of reference. But what if you’re just now learning to use a relational database? Yes, you’ve played with Access a bit, but now your employer or college instructor has charged you with becoming proficient with Oracle database. Here’s 10 reasons why I think Oracle SQL Developer is the perfect vehicle to help get you started. 1. It’s free No need to break into one of these… No start-up costs, no need to wrangle budget dollars from your company. Students don’t have any money after books and lab fees anyway. And most employees don’t like having to ask for ‘special’ software anyway. So avoid all of that and make sure the free stuff doesn’t suit your needs first. Upgrades are available on a regular base, also at no cost, and support is freely available via our public forums. 2. It will run pretty much anywhere Windows – check. OSX (Apple) – check. Unix – check. Linux – check. No need to start up a windows VM to run your Windows-only software in your lab machine. 3. Anyone can install it There’s no installer, no registry to be updated, no admin privs to be obtained. If you can download and extract files to your machine or USB storage device, you can run it. You can be up and running with SQL Developer in under 5 minutes. Here’s a video tutorial to see how to get started. 4. It’s ubiquitous I admit it, I learned a new word yesterday and I wanted an excuse to use it. SQL Developer’s everywhere. It’s had over 2,500,000 downloads in the past year, and is the one of the most downloaded items from OTN. This means if you need help, there’s someone sitting nearby you that can assist, and since they’re in the same tool as you, they’ll be speaking the same language. 5. Simple User Interface Up-up-down-down-Left-right-left-right-A-B-A-B-START will get you 30 lives, but you already knew that, right? You connect, you see your objects, you click on your objects. Or, you can use the worksheet to write your queries and programs in. There’s only one toolbar, and just a few buttons. If you’re like me, video games became less fun when each button had 6 action items mapped to it. I just want the good ole ‘A’, ‘B’, ‘SELECT’, and ‘START’ controls. If you’re new to Oracle, you shouldn’t have the double-workload of learning a new complicated tool as well. 6. It’s not a ‘black box’ Click through your objects, but also get the SQL that drives the GUI As you use the wizards to accomplish tasks for you, you can view the SQL statement being generated on your behalf. Just because you have a GUI, doesn’t mean you’re ceding your responsibility to learn the underlying code that makes the database work. 7. It’s four tools in one It’s not just a query tool. Maybe you need to design a data model first? Or maybe you need to migrate your Sybase ASE database to Oracle for a new project? Or maybe you need to create some reports? SQL Developer does all of that. So once you get comfortable with one part of the tool, the others will be much easier to pick up as your needs change. 8. Great learning resources available Videos, blogs, hands-on learning labs – you name it, we got it. Why wait for someone to train you, when you can train yourself at your own pace? 9. You can use it to teach yourself SQL Instead of being faced with the white-screen-of-panic, you can visually build your queries by dragging and dropping tables and views into the Query Builder. Yes, ‘just like Access’ – only better. And as you build your query, toggle to the Worksheet panel and see the SQL statement. Again, SQL Developer is not a black box. If you prefer to learn by trial and error, the worksheet will attempt to suggest the next bit of your SQL statement with it’s completion insight feature. And if you have syntax errors, those will be highlighted – just like your misspelled words in your favorite word processor. 10. It scales to match your experience level You won’t be a n00b forever. In 6-8 months, when you’re ready to tackle something a bit more complicated, like XML DB or Oracle Spatial, the tool is already there waiting on you. No need to go out and find the ‘advanced’ tool. 11. Wait, you said this was a ‘Top 10′ list? Yes. Yes, I did. I’m using this ‘trick’ to get you to continue reading because I’m going to say something you might not want to hear. Are you ready? Tools won’t replace experience, failure, hard work, and training. Just because you have the keys to the car, doesn’t mean you’re ready to head out on the race track. While SQL Developer reduces the barriers to entry, it does not completely remove them. Many experienced folks simply do not like tools. Rather, they don’t like the people that pick up tools without the know-how to properly use them. If you don’t understand what ‘TRUNCATE’ means, don’t try it out. Try picking up a book first. Of course, it’s very nice to have your own sandbox to play in, so you don’t upset the other children. That’s why I really like our Dev Days Database Virtual Box image. It’s your own database to learn and experiment with.

    Read the article

  • Parallelism in .NET – Part 6, Declarative Data Parallelism

    - by Reed
    When working with a problem that can be decomposed by data, we have a collection, and some operation being performed upon the collection.  I’ve demonstrated how this can be parallelized using the Task Parallel Library and imperative programming using imperative data parallelism via the Parallel class.  While this provides a huge step forward in terms of power and capabilities, in many cases, special care must still be given for relative common scenarios. C# 3.0 and Visual Basic 9.0 introduced a new, declarative programming model to .NET via the LINQ Project.  When working with collections, we can now write software that describes what we want to occur without having to explicitly state how the program should accomplish the task.  By taking advantage of LINQ, many operations become much shorter, more elegant, and easier to understand and maintain.  Version 4.0 of the .NET framework extends this concept into the parallel computation space by introducing Parallel LINQ. Before we delve into PLINQ, let’s begin with a short discussion of LINQ.  LINQ, the extensions to the .NET Framework which implement language integrated query, set, and transform operations, is implemented in many flavors.  For our purposes, we are interested in LINQ to Objects.  When dealing with parallelizing a routine, we typically are dealing with in-memory data storage.  More data-access oriented LINQ variants, such as LINQ to SQL and LINQ to Entities in the Entity Framework fall outside of our concern, since the parallelism there is the concern of the data base engine processing the query itself. LINQ (LINQ to Objects in particular) works by implementing a series of extension methods, most of which work on IEnumerable<T>.  The language enhancements use these extension methods to create a very concise, readable alternative to using traditional foreach statement.  For example, let’s revisit our minimum aggregation routine we wrote in Part 4: double min = double.MaxValue; foreach(var item in collection) { double value = item.PerformComputation(); min = System.Math.Min(min, value); } .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; } Here, we’re doing a very simple computation, but writing this in an imperative style.  This can be loosely translated to English as: Create a very large number, and save it in min Loop through each item in the collection. For every item: Perform some computation, and save the result If the computation is less than min, set min to the computation Although this is fairly easy to follow, it’s quite a few lines of code, and it requires us to read through the code, step by step, line by line, in order to understand the intention of the developer. We can rework this same statement, using LINQ: double min = collection.Min(item => item.PerformComputation()); Here, we’re after the same information.  However, this is written using a declarative programming style.  When we see this code, we’d naturally translate this to English as: Save the Min value of collection, determined via calling item.PerformComputation() That’s it – instead of multiple logical steps, we have one single, declarative request.  This makes the developer’s intentions very clear, and very easy to follow.  The system is free to implement this using whatever method required. Parallel LINQ (PLINQ) extends LINQ to Objects to support parallel operations.  This is a perfect fit in many cases when you have a problem that can be decomposed by data.  To show this, let’s again refer to our minimum aggregation routine from Part 4, but this time, let’s review our final, parallelized version: // Safe, and fast! double min = double.MaxValue; // Make a "lock" object object syncObject = new object(); Parallel.ForEach( collection, // First, we provide a local state initialization delegate. () => double.MaxValue, // Next, we supply the body, which takes the original item, loop state, // and local state, and returns a new local state (item, loopState, localState) => { double value = item.PerformComputation(); return System.Math.Min(localState, value); }, // Finally, we provide an Action<TLocal>, to "merge" results together localState => { // This requires locking, but it's only once per used thread lock(syncObj) min = System.Math.Min(min, localState); } ); Here, we’re doing the same computation as above, but fully parallelized.  Describing this in English becomes quite a feat: Create a very large number, and save it in min Create a temporary object we can use for locking Call Parallel.ForEach, specifying three delegates For the first delegate: Initialize a local variable to hold the local state to a very large number For the second delegate: For each item in the collection, perform some computation, save the result If the result is less than our local state, save the result in local state For the final delegate: Take a lock on our temporary object to protect our min variable Save the min of our min and local state variables Although this solves our problem, and does it in a very efficient way, we’ve created a set of code that is quite a bit more difficult to understand and maintain. PLINQ provides us with a very nice alternative.  In order to use PLINQ, we need to learn one new extension method that works on IEnumerable<T> – ParallelEnumerable.AsParallel(). That’s all we need to learn in order to use PLINQ: one single method.  We can write our minimum aggregation in PLINQ very simply: double min = collection.AsParallel().Min(item => item.PerformComputation()); By simply adding “.AsParallel()” to our LINQ to Objects query, we converted this to using PLINQ and running this computation in parallel!  This can be loosely translated into English easily, as well: Process the collection in parallel Get the Minimum value, determined by calling PerformComputation on each item Here, our intention is very clear and easy to understand.  We just want to perform the same operation we did in serial, but run it “as parallel”.  PLINQ completely extends LINQ to Objects: the entire functionality of LINQ to Objects is available.  By simply adding a call to AsParallel(), we can specify that a collection should be processed in parallel.  This is simple, safe, and incredibly useful.

    Read the article

  • HTTP Push from SQL Server — Comet SQL

    Article provides example solution for presenting data in "real-time" from Microsoft SQL Server in HTML browser. Article presents how to implement Comet functionality in ASP.NET and how to connect Comet with Query Notification from SQL Server.

    Read the article

  • Using linked servers, OPENROWSET and OPENQUERY

    - by BuckWoody
    SQL Server has a few mechanisms to reach out to another server (even another server type) and query data from within a Transact-SQL statement. Among them are a set of stored credentials and information (called a Linked Server), a statement that uses a linked server called called OPENQUERY, another called OPENROWSET, and one called OPENDATASOURCE. This post isn’t about those particular functions or statements – hit the links for more if you’re new to those topics. I’m actually more concerned about where I see these used than the particular method. In many cases, a Linked server isn’t another Relational Database Management System (RDMBS) like Oracle or DB2 (which is possible with a linked server), but another SQL Server. My concern is that linked servers are the new Data Transformation Services (DTS) from SQL Server 2000 – something that was designed for one purpose but which is being morphed into something much more. In the case of DTS, most of us turned that feature into a full-fledged job system. What was designed as a simple data import and export system has been pressed into service doing logic, routing and timing. And of course we all know how painful it was to move off of a complex DTS system onto SQL Server Integration Services. In the case of linked servers, what should be used as a method of running a simple query or two on another server where you have occasional connection or need a quick import of a small data set is morphing into a full federation strategy. In some cases I’ve seen a complex web of linked servers, and when credentials, names or anything else changes there are huge problems. Now don’t get me wrong – linked servers and other forms of distributing queries is a fantastic set of tools that we have to move data around. I’m just saying that when you start having lots of workarounds and when things get really complicated, you might want to step back a little and ask if there’s a better way. Are you able to tolerate some latency? Perhaps you’re able to use Service Broker. Would you like to be platform-independent on the data source? Perhaps a middle-tier might make more sense, abstracting the queries there and sending them to the proper server. Designed properly, I’ve seen these systems scale further and be more resilient than loading up on linked servers. Share this post: email it! | bookmark it! | digg it! | reddit! | kick it! | live it!

    Read the article

< Previous Page | 382 383 384 385 386 387 388 389 390 391 392 393  | Next Page >