Left Outer Join against another table in the database.
$table: The table against which to join.
$alias: The alias for the table. In most cases this should be the first letter of the table, or the first letter of each "word" in the table.
$condition: The condition on which to join this table. If the join requires values, this clause should use a named placeholder and the value or values to insert should be passed in the 4th parameter. For the first table joined on a query, this value is ignored as the first table is taken as the base table. The token %alias can be used in this string to be replaced with the actual alias. This is useful when $alias is modified by the database system, for example, when joining the same table more than once.
$arguments: An array of arguments to replace into the $condition of this join.
string: The unique alias that was assigned for this table.
includes/ database/ select.inc, line 316
- Interface definition for a Select Query object.
public function leftJoin($table, $alias = NULL, $condition = NULL, $arguments = array());