sql-table-prefixes.rst

SQL-Table Prefixes

This recipe is intended as an example of implementing a loadClassMetadata listener to provide a Table Prefix option for your application. The method used below is not a hack, but fully integrates into the Doctrine system, all SQL generated will include the appropriate table prefix.

In most circumstances it is desirable to separate different applications into individual databases, but in certain cases, it may be beneficial to have a table prefix for your Entities to separate them from other vendor products in the same database.

Implementing the listener

The listener in this example has been set up with the DoctrineExtensions namespace. You create this file in your library/DoctrineExtensions directory, but will need to set up appropriate autoloaders.

<?php

namespace DoctrineExtensions;
use \Doctrine\ORM\Event\LoadClassMetadataEventArgs;

class TablePrefix
{
    protected $prefix = '';

    public function __construct($prefix)
    {
        $this->prefix = (string) $prefix;
    }

    public function loadClassMetadata(LoadClassMetadataEventArgs $eventArgs)
    {
        $classMetadata = $eventArgs->getClassMetadata();
        $classMetadata->setTableName($this->prefix . $classMetadata->getTableName());
        foreach ($classMetadata->getAssociationMappings() as $fieldName => $mapping) {
            if ($mapping['type'] == \Doctrine\ORM\Mapping\ClassMetadataInfo::MANY_TO_MANY) {
                $mappedTableName = $classMetadata->associationMappings[$fieldName]['joinTable']['name'];
                $classMetadata->associationMappings[$fieldName]['joinTable']['name'] = $this->prefix . $mappedTableName;
            }
        }
    }

}

Telling the EntityManager about our listener

A listener of this type must be set up before the EntityManager has been initialised, otherwise an Entity might be created or cached before the prefix has been set.

Note

If you set this listener up, be aware that you will need to clear your caches and drop then recreate your database schema.

<?php

// $connectionOptions and $config set earlier

$evm = new \Doctrine\Common\EventManager;

// Table Prefix
$tablePrefix = new \DoctrineExtensions\TablePrefix('prefix_');
$evm->addEventListener(\Doctrine\ORM\Events::loadClassMetadata, $tablePrefix);

$em = \Doctrine\ORM\EntityManager::create($connectionOptions, $config, $evm);