src/Storage/PDOConnector.php
public function prepare(string $sql): ?\PDOStatement {
        $statement = $this->getConnection()->prepare($sql);
        if ($statement === false) {
            return null;
        }
        $this->statement = $statement;
        return $statement;
    }
public function prepare(string $sql): ?\PDOStatement {
        $statement = $this->getConnection()->prepare($sql);
        if ($statement === false) {
            return null;
        }
        $this->statement = $statement;
        return $statement;
    }
public function prepare ( string $ sql ) : ? \ PDOStatement { $ statement = $ this -> getConnection ( ) -> prepare ( $ sql ) ; if ( $ statement === false ) { return null ; } $ this -> statement = $ statement ; return $ statement ; }
prepares a SQL statement

@param string $sql
@return null|\PDOStatement
prepares a SQL statement