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Top Forums Shell Programming and Scripting Select record with MAX value in MySQL Post 302433426 by radoulov on Tuesday 29th of June 2010 03:39:50 PM
Old 06-29-2010
Quote:
In the real world, I have a big table containing a huge number of uploaded files.[...]
Well,
first of all, I think, you should rethink the relational design.
 

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CGI::Session::Driver::mysql(3pm)			User Contributed Perl Documentation			  CGI::Session::Driver::mysql(3pm)

NAME
CGI::Session::Driver::mysql - CGI::Session driver for MySQL database SYNOPSIS
$s = CGI::Session->new( 'driver:mysql', $sid); $s = CGI::Session->new( 'driver:mysql', $sid, { DataSource => 'dbi:mysql:test', User => 'sherzodr', Password => 'hello' }); $s = CGI::Session->new( 'driver:mysql', $sid, { Handle => $dbh } ); DESCRIPTION
mysql stores session records in a MySQL table. For details see CGI::Session::Driver::DBI, its parent class. It's especially important for the MySQL driver that the session ID column be defined as a primary key, or at least "unique", like this: CREATE TABLE sessions ( id CHAR(32) NOT NULL PRIMARY KEY, a_session TEXT NOT NULL ); To use different column names, change the 'create table' statement, and then simply do this: $s = CGI::Session->new('driver:mysql', undef, { TableName=>'session', IdColName=>'my_id', DataColName=>'my_data', DataSource=>'dbi:mysql:project', }); or $s = CGI::Session->new('driver:mysql', undef, { TableName=>'session', IdColName=>'my_id', DataColName=>'my_data', Handle=>$dbh, }); DRIVER ARGUMENTS mysql driver supports all the arguments documented in CGI::Session::Driver::DBI. In addition, DataSource argument can optionally leave leading "dbi:mysql:" string out: $s = CGI::Session->new( 'driver:mysql', $sid, {DataSource=>'shopping_cart'}); # is the same as: $s = CGI::Session->new( 'driver:mysql', $sid, {DataSource=>'dbi:mysql:shopping_cart'}); BACKWARDS COMPATIBILITY As of V 4.30, the global variable $CGI::Session::MySQL::TABLE_NAME cannot be used to set the session table's name. This is due to changes in CGI::Session::Driver's new() method, which now allows the table's name to be changed (as well as allowing both the 'id' column name and the 'a_session' column name to be changed). See the documentation for CGI::Session::Driver::DBI for details. In particular, the new syntax for "new()" applies to all database drivers, whereas the old - and bad - global variable method only applied to MySQL. Alternately, call $session -> table_name('new_name') just after creating the session object if you wish to change the session table's name. LICENSING
For support and licensing see CGI::Session. perl v5.12.4 2011-07-08 CGI::Session::Driver::mysql(3pm)
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