src/Query/SelectQuery.php
public function union(self $query, $type = '')
    {
        $this->union->addQuery($query, $type);

        return $this;
    }
public function union(self $query, $type = '')
    {
        $this->union->addQuery($query, $type);

        return $this;
    }
public function union ( self $ query , $ type = '' ) { $ this -> union -> addQuery ( $ query , $ type ) ; return $ this ; }
Unions another select query with this query.

@param SelectQuery $query
@param string      $type  optional union type

@return self
Unions another select query with this query .