src/Query/FluentQuery.php
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