Represent an OVER clause. This is a special operator against a so-called "window" function, as well as any aggregate function, which produces results relative to the result set itself. Most modern SQL backends now support window functions.
| 4509 | |
| 4510 | |
| 4511 | class Over(ColumnElement[_T]): |
| 4512 | """Represent an OVER clause. |
| 4513 | |
| 4514 | This is a special operator against a so-called |
| 4515 | "window" function, as well as any aggregate function, |
| 4516 | which produces results relative to the result set |
| 4517 | itself. Most modern SQL backends now support window functions. |
| 4518 | |
| 4519 | """ |
| 4520 | |
| 4521 | __visit_name__ = "over" |
| 4522 | |
| 4523 | _traverse_internals: _TraverseInternalsType = [ |
| 4524 | ("element", InternalTraversal.dp_clauseelement), |
| 4525 | ("order_by", InternalTraversal.dp_clauseelement), |
| 4526 | ("partition_by", InternalTraversal.dp_clauseelement), |
| 4527 | ("range_", InternalTraversal.dp_clauseelement), |
| 4528 | ("rows", InternalTraversal.dp_clauseelement), |
| 4529 | ("groups", InternalTraversal.dp_clauseelement), |
| 4530 | ("exclude", InternalTraversal.dp_string), |
| 4531 | ] |
| 4532 | |
| 4533 | order_by: Optional[ClauseList] = None |
| 4534 | partition_by: Optional[ClauseList] = None |
| 4535 | |
| 4536 | element: ColumnElement[_T] |
| 4537 | """The underlying expression object to which this :class:`.Over` |
| 4538 | object refers.""" |
| 4539 | |
| 4540 | range_: FrameClause | None |
| 4541 | rows: FrameClause | None |
| 4542 | groups: FrameClause | None |
| 4543 | exclude: str | None |
| 4544 | |
| 4545 | def __init__( |
| 4546 | self, |
| 4547 | element: ColumnElement[_T], |
| 4548 | partition_by: Optional[_ByArgument] = None, |
| 4549 | order_by: Optional[_ByArgument] = None, |
| 4550 | range_: _FrameIntTuple | FrameClause | None = None, |
| 4551 | rows: _FrameIntTuple | FrameClause | None = None, |
| 4552 | groups: _FrameIntTuple | FrameClause | None = None, |
| 4553 | exclude: str | None = None, |
| 4554 | ): |
| 4555 | self.element = element |
| 4556 | if order_by is not None: |
| 4557 | self.order_by = ClauseList( |
| 4558 | *util.to_list(order_by), _literal_as_text_role=roles.ByOfRole |
| 4559 | ) |
| 4560 | if partition_by is not None: |
| 4561 | self.partition_by = ClauseList( |
| 4562 | *util.to_list(partition_by), |
| 4563 | _literal_as_text_role=roles.ByOfRole, |
| 4564 | ) |
| 4565 | |
| 4566 | if sum(item is not None for item in (range_, rows, groups)) > 1: |
| 4567 | raise exc.ArgumentError( |
| 4568 | "only one of 'rows', 'range_', or 'groups' may be provided" |