private function _join(JoinClause $join, $table, $sourceField, $destField = null, $where = null)
{
/**
* @var $this IStatement
*/
if ($destField === null) {
$destField = $sourceField;
}
$from = $this->getClause('FROM');
if ($from instanceof FromClause) {
$sourceTable = $from->getTable();
if ($sourceTable instanceof TableSelectExpression) {
/** @var TableSelectExpression $sourceTable */
$sourceTable = $sourceTable->getAlias();
} else {
if ($sourceTable instanceof TableExpression) {
/** @var TableExpression $sourceTable */
$sourceTable = $sourceTable->getTableName();
}
}
} else {
throw new \RuntimeException("Unable to join on a statement without a from clause being specified");
}
$join->setTableName($table);
$join->setDestinationField($table, $destField);
$join->setSourceField($sourceTable, $sourceField);
if ($where !== null) {
$join->setPredicates(WhereClause::buildPredicates($where, $table));
}
$this->addClause($join);
return $this;
}