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Class-DBI-mysql-0.04
River stage one • 2 direct dependents • 2 total dependents
/ Class::DBI::mysql

NAME

Class::DBI::mysql - Extensions to Class::DBI for MySQL

SYNOPSIS

  package Film.pm;
  use base 'Class::DBI::mysql';
  __PACKAGE__->set_db('Main', 'dbi:mysql', 'user', 'password');
  __PACKAGE__->set_up_table("film");

  # Somewhere else ...

  $howmany = Film->count;

  @all_films = Film->retrieve_all;
  $tonights_viewing  = Film->retrieve_random;

  @results = Film->search_match($key => $value);

DESCRIPTION

This is an extension to Class::DBI, containing several functions and optimisations for the MySQL database. Instead of setting Class::DBI as your base class, use this instead.

set_up_table

  __PACKAGE__->set_up_table("table_name");

Traditionally, to use Class::DBI, you have to set up the columns:

  __PACKAGE__->columns(All => qw/list of columns/);
  __PACKAGE__->columns(Primary => 'column_name');

Whilst this allows for more flexibility if you're going to arrange your columns into a variety of groupings, sometimes you just want to create the 'all columns' list. Well, this information is really simple to extract from MySQL itself, so why not just use that?

This call will extract the list of all the columns, and the primary key and set them up for you. It will die horribly if the table contains no primary key, or has a composite primary key.

count

  $howmany = Film->count;

This will count how many of these there are. You could get the same effect by doing a 'select all', but this avoids the overhead of having to fetch them all back by using MySQL's highly optimised COUNT(*) function instead.

retrieve_all

  @films = Film->retrieve_all;

This will return you a list of objects - one for each of the rows in your table.

retrieve_random

  my $film = Film->retrieve_random;

This will select a random row from the database, and return you the relevant object.

(MySQL 3.23 and higher only, at this point)

search_match

  @results = Film->search_match($key => $value);

This is like search, but using the MySQL 'full text matching' capabilities.

CURDATE() / CURTIME() / NOW()

Due to the way in which placeholders work under DBI, it's currently very difficult to translate a query like the following to Class::DBI

  UPDATE foo
     SET flibble = "bar", since = CURDATE()

Rather than having to convert all your columns to timestamps, this module allows you to specify CURDATE(), CURTIME() or NOW() as values:

  $foo->flibble("bar") and $foo->since("CURDATE()") and $foo->commit;

CAVEAT: Note that until you've called 'commit', the value of this field will be set to this string, and not the translation of it. For objects which are going to make use of this feature, consider turning autocommit on.

COPYRIGHT

Copyright (C) 2001 Tony Bowden. All rights reserved.

This library is free software; you can redistribute it and/or modify it under the same terms as Perl itself.

AUTHOR

Tony Bowden, <tony@tmtm.com>.

SEE ALSO

Class::DBI. MySQL (http://www.mysql.com/)