How do I get Drupal to use table prefixes so I can install multiple drupal installations in the same database schema?

Question

My webhost is pretty limited, and I only have one database user & schema. I would like to install multiple drupal installations on this database schema.

How do I tell each installation to prefix its tablenames with a given string?

Answer 1

In the settings.php file, a normal setup might look like

$databases['default']['default'] = array(
  'driver' => 'mysql',
  'database' => 'databasename',
  'username' => 'username',
  'password' => 'password',
  'host' => 'localhost',
  'collation' => 'utf8_general_ci',
);

The only difference is that you add a 'prefix', like this:

$databases['default']['default'] = array(
  'driver' => 'mysql',
  'database' => 'databasename',
  'username' => 'username',
  'password' => 'password',
  'host' => 'localhost',
  'prefix' => 'site1_',
  'collation' => 'utf8_general_ci',
);

Make the prefix different in each settings.php site, and you can have as many sites as you want within the same database.