final public function queryOnString(string $query, string $default = '', string $separator = ', '): string
    {
        $array = $this->queryArrayOne($query);
        if (false === $array) {
            return $default;
        }
        return implode($separator, $array);
    }
final public function queryOnString(string $query, string $default = '', string $separator = ', '): string
    {
        $array = $this->queryArrayOne($query);
        if (false === $array) {
            return $default;
        }
        return implode($separator, $array);
    }
final public function queryOnString ( string $ query , string $ default = '' , string $ separator = ', ' ) : string { $ array = $ this -> queryArrayOne ( $ query ) ; if ( false === $ array ) { return $ default ; } return implode ( $ separator , $ array ) ; }
Return the result of the query as a imploded string with all the values of the first column

@param string $query
@param string $default
@param string $separator
@return string
Return the result of the query as a imploded string with all the values of the first column