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If you have basic understanding of apache, then this article is highly recommended for setup: http://httpd.apache.org/docs/1.3/howto/cgi.html I did setup this in my mac/OSx, was not easy to find info on web, hence I am briefing out the flow: 1) uncomment "LoadModule cgi_module libexec/apache2/mod_cgi.so" ( for me it exists in httpd.conf ) 2) edit virtual hosts file to look like this: ( for mac, it is in httpd-vhosts.conf ) Options Indexes MultiViews FollowSymLinks ExecCGI AllowOverride All Order allow,deny Allow from all NOTE: "/www" is where my project resides "ExecCGI" is the option that has to be there 3) Below the directory closing, add this line: ( for mac, it is in httpd-vhosts.conf ) AddHandler cgi-script cgi py 4) Restart apache: "sudo apachectl restart" Now running your project should give "End of script output before headers" error in

sometimes you're caught up in a situation where you have multiple entries against an id and you want to keep only single entry against each. Table structure would be something like this: Table `temp` Entries: user_id tstamp source 100 4/26/2015 app 100 4/26/2014 web 100 4/25/2015 app 101 4/26/2015 app 100 4/23/2015 app 101 4/20/2015 web 100 4/1/2015 app 200 4/26/2015 app 200 4/2/2015 app Desired Output: user_id tstamp source 100 4/26/2015 app 100 4/26/2014 web 101 4/26/2015 app 200 4/26/2015 app Now, I want to delete the rows where source is `app` and keep the entry with max tstamp only with in a group. Here's the sample query to achieve the same: DELETE tmp FROM `temp` tmp join (select user_id, max(tstamp) as ts from `temp` where user_id in (select user_id from `temp` where source = 'app' group by user_id having count(user_id)>2) and source = 'app' group by user_id )t on tmp.user_id = t.user_id and tmp.tstamp != t.t

If you want to access a private variable/method outside the class... here is a trick to do the same: class A { private $notVisibleOutside = 1; } $a = new ReflectionClass("A"); $property = $class->getProperty("notVisibleOutside "); $property->setAccessible(true); $a1 = new A(); echo $property->getValue($a1); // Work So, the basic idea is to - create a reflection class in php - make the property or method accessible - use that property to access the private variables/methods

update table temp set `a`=`a`+1 , `b`= `a`+ 1; this query sometimes doesn't yield the result we are actually looking for.. so the problem is `a` is getting updated first. So, the actual query should be : update table temp set `b`= `a`+ 1, `a`=`a`+1 ;

redis-cli keys "sess*" | while read LINE ;do echo `redis-cli EXPIRE $LINE 10000`; done; NOTE: "sess*" will be replaced by the key name and 10000 will be replaced by time you want to set for expiry (will be in seconds)

A basic and fairly easy way to do mass insert in redis : Command to use: echo -e "$(cat redis_mass_insert.txt)" | redis-cli --pipe Content of file "redis_mass_insert.txt": *3\r\n$5\r\nlpush\r\n$5\r\nu:m:1\r\n$5\r\nvalu1\r\n*3\r\n$5\r\nlpush\r\n$5\r\nu:m:1\r\n$7\r\nmyvalue\r\n Result: All data transferred. Waiting for the last reply... ERR unknown command ' *2' ERR unknown command '$4' ERR wrong number of arguments for 'echo' command ERR unknown command '$20' ERR unknown command ' A�j d�Q;yT��ҡ �h>' NOTE: command line will show error but in actual the data is transferred and you can check it by entering in redis. Here's the snapshot of the whole procedure: To check how the command is responding: use hexdump -C Command: echo -n $'$3\r\nset\r\n$3\r\nkey\r\n$5\r\nvalue\r\n ' | hexdump -C whose output will be something like 00000000 24 33 0d 0a 73 65 74 0d 0a 24 33 0d 0a 6b 65 79 |$3..set..