Module datafusion_expr::window_frame

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Window frame module

The frame-spec determines which output rows are read by an aggregate window function. The frame-spec consists of four parts:

  • A frame type - either ROWS, RANGE or GROUPS,
  • A starting frame boundary,
  • An ending frame boundary,
  • An EXCLUDE clause.

Structs

  • WindowFrame
    The frame-spec determines which output rows are read by an aggregate window function.

Enums

  • WindowFrameBound
    There are five ways to describe starting and ending frame boundaries:
  • WindowFrameUnits
    There are three frame types: ROWS, GROUPS, and RANGE. The frame type determines how the starting and ending boundaries of the frame are measured.

Functions

  • convert_frame_bound_to_scalar_value
  • regularize
    Construct equivalent explicit window frames for implicit corner cases. With this processing, we may assume in downstream code that RANGE/GROUPS frames contain an appropriate ORDER BY clause.