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NAME

Mojo::mysql - Mojolicious and Async MySQL

SYNOPSIS

  use Mojo::mysql;

  # Create a table
  my $mysql = Mojo::mysql->new('mysql://username@/test');
  $mysql->db->do('create table if not exists names (name text)');

  # Insert a few rows
  my $db = $mysql->db;
  $db->query('insert into names values (?)', 'Sara');
  $db->query('insert into names values (?)', 'Daniel');

  # Select all rows blocking
  say for $db->query('select * from names')
    ->hashes->map(sub { $_->{name} })->each;

  # Select all rows non-blocking
  Mojo::IOLoop->delay(
    sub {
      my $delay = shift;
      $db->query('select * from names' => $delay->begin);
    },
    sub {
      my ($delay, $err, $results) = @_;
      say for $results->hashes->map(sub { $_->{name} })->each;
    }
  )->wait;

DESCRIPTION

Mojo::mysql is a tiny wrapper around DBD::mysql that makes MySQL a lot of fun to use with the Mojolicious real-time web framework.

Database handles are cached automatically, so they can be reused transparently to increase performance. While all I/O operations are performed blocking, you can wait for long running queries asynchronously, allowing the Mojo::IOLoop event loop to perform other tasks in the meantime. Since database connections usually have a very low latency, this often results in very good performance.

All cached database handles will be reset automatically if a new process has been forked, this allows multiple processes to share the same Mojo::mysql object safely.

Note that this whole distribution is EXPERIMENTAL and will change without warning!

EVENTS

Mojo::mysql inherits all events from Mojo::EventEmitter and can emit the following new ones.

connection

  $mysql->on(connection => sub {
    my ($mysql, $dbh) = @_;
    ...
  });

Emitted when a new database connection has been established.

ATTRIBUTES

Mojo::mysql implements the following attributes.

dsn

  my $dsn = $mysql->dsn;
  $mysql  = $mysql->dsn('dbi:mysql:dbname=foo');

Data Source Name, defaults to dbi:mysql:dbname=test.

max_connections

  my $max = $mysql->max_connections;
  $mysql  = $mysql->max_connections(3);

Maximum number of idle database handles to cache for future use, defaults to 5.

migrations

MySQL does not support DDL transactions. Therefore, migrations should be used with extreme caution. Backup your database. You've been warned.

  my $migrations = $mysql->migrations;
  $mysql         = $mysql->migrations(Mojo::mysql::Migrations->new);

Mojo::mysql::Migrations object you can use to change your database schema more easily.

  # Load migrations from file and migrate to latest version
  $mysql->migrations->from_file('/Users/sri/migrations.sql')->migrate;

options

  my $options = $mysql->options;
  $mysql      = $mysql->options({mysql_use_result => 1});

Options for database handles, defaults to activating mysql_enable_utf8, AutoCommit as well as RaiseError and deactivating PrintError.

mysql_auto_reconnect is never enabled, Mojo::mysql takes care of dead connections.

AutoCommit cannot not be disabled, use $db->begin to manage transactions.

RaiseError is disabled in event loop for asyncronous queries.

password

  my $password = $mysql->password;
  $mysql       = $mysql->password('s3cret');

Database password, defaults to an empty string.

username

  my $username = $mysql->username;
  $mysql       = $mysql->username('batman');

Database username, defaults to an empty string.

METHODS

Mojo::mysql inherits all methods from Mojo::EventEmitter and implements the following new ones.

db

  my $db = $mysql->db;

Get Mojo::mysql::Database object for a cached or newly created database handle. The database handle will be automatically cached again when that object is destroyed, so you can handle connection timeouts gracefully by holding on to it only for short amounts of time.

from_string

  $mysql = $mysql->from_string('mysql://user@/test');

Parse configuration from connection string.

  # Just a database
  $mysql->from_string('mysql:///db1');

  # Username and database
  $mysql->from_string('mysql://batman@/db2');

  # Username, password, host and database
  $mysql->from_string('mysql://batman:s3cret@localhost/db3');

  # Username, domain socket and database
  $mysql->from_string('mysql://batman@%2ftmp%2fmysql.sock/db4');

  # Username, database and additional options
  $mysql->from_string('mysql://batman@/db5?PrintError=1&RaiseError=0');

new

  my $mysql = Mojo::mysql->new;
  my $mysql = Mojo::mysql->new('mysql://user@/test');

Construct a new Mojo::mysql object and parse connection string with "from_string" if necessary.

AUTHOR

Curt Hochwender, hochwender@centurytel.net.

Jan Henning Thorsen, jhthorsen@cpan.org.

This code is mostly a rip-off from Sebastian Riedel's Mojo::Pg.

COPYRIGHT AND LICENSE

Copyright (C) 2014, Jan Henning Thorsen.

This program is free software, you can redistribute it and/or modify it under the terms of the Artistic License version 2.0.

SEE ALSO

Mojo::Pg, https://github.com/jhthorsen/mojo-mysql, Mojolicious::Guides, http://mojolicio.us.