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Top Forums Programming Getting Rows from a MySQL Table with max values? Post 302633861 by Corona688 on Wednesday 2nd of May 2012 02:40:39 PM
Old 05-02-2012
Quote:
Originally Posted by 47shailesh
If we do "order by" than index is required.
I've fixed extremely slow order-by queries by adding appropriate indexes before; without them, it was forced to do a table scan, save to a temporary table, and sort after-the-fact, each step of which I could watch individually with the appropriate commands(something like 'show query status').

"Very poor performance" is not the same thing as "doesn't work at all".
 

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DBIx::Class::Storage::DBI::mysql(3)			User Contributed Perl Documentation		       DBIx::Class::Storage::DBI::mysql(3)

NAME
DBIx::Class::Storage::DBI::mysql - Storage::DBI class implementing MySQL specifics SYNOPSIS
Storage::DBI autodetects the underlying MySQL database, and re-blesses the $storage object into this class. my $schema = MyApp::Schema->connect( $dsn, $user, $pass, { on_connect_call => 'set_strict_mode' } ); DESCRIPTION
This class implements MySQL specific bits of DBIx::Class::Storage::DBI, like AutoIncrement column support and savepoints. Also it augments the SQL maker to support the MySQL-specific "STRAIGHT_JOIN" join type, which you can use by specifying "join_type => 'straight'" in the relationship attributes It also provides a one-stop on-connect macro "set_strict_mode" which sets session variables such that MySQL behaves more predictably as far as the SQL standard is concerned. STORAGE OPTIONS
set_strict_mode Enables session-wide strict options upon connecting. Equivalent to: ->connect ( ... , { on_connect_do => [ q|SET SQL_MODE = CONCAT('ANSI,TRADITIONAL,ONLY_FULL_GROUP_BY,', @@sql_mode)|, q|SET SQL_AUTO_IS_NULL = 0|, ] }); AUTHORS
See "CONTRIBUTORS" in DBIx::Class LICENSE
You may distribute this code under the same terms as Perl itself. perl v5.18.2 2014-01-22 DBIx::Class::Storage::DBI::mysql(3)
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