Get the join object that should be used for this handler.
This method isn't used a great deal, but it's very handy for easily getting the join if it is necessary to make some changes to it, such as adding an 'extra'.
public function getJoin() {
// get the join from this table that links back to the base table.
// Determine the primary table to seek
if (empty($this->query->relationships[$this->relationship])) {
$base_table = $this->view->storage
->get('base_table');
}
else {
$base_table = $this->query->relationships[$this->relationship]['base'];
}
$join = $this
->getTableJoin($this->table, $base_table);
if ($join) {
return clone $join;
}
}