public function group_by( $column ) {

		$column = $this->prepare_column( $column );

		if ( is_null( $this->group ) ) {
			$this->group = new Group( $column );
		} else {
			$this->group->then( $column );
		}

		return $this;
	}
public function group_by( $column ) {

		$column = $this->prepare_column( $column );

		if ( is_null( $this->group ) ) {
			$this->group = new Group( $column );
		} else {
			$this->group->then( $column );
		}

		return $this;
	}
public function group_by ( $ column ) { $ column = $ this -> prepare_column ( $ column ) ; if ( is_null ( $ this -> group ) ) { $ this -> group = new Group ( $ column ) ; } else { $ this -> group -> then ( $ column ) ; } return $ this ; }
Group the results by a given column.

Can be called multiple times to add additional group by columns.

@since 2.0

@param string $column

@return $this

@throws \IronBound\DB\Exception\InvalidColumnException
Group the results by a given column .