Module scan_plan 

ScanPlan: the byte ranges that a push decoder may still read.

Modules

budget 🔒

Offset/limit budget shared across the row groups of a scan.

frontier 🔒

Which row groups a scan reads next, with their selections and budget.

Structs

PlannedRange

One item of a ScanPlan.

Planner 🔒

The state of a ScanPlan that is not empty.

RowGroupContext 🔒

What the ranges of one row group are computed from.

RowGroupRanges 🔒

The planned ranges of one row group, in decode order.

ScanPlan

The byte ranges that a push decoder may still read, in the order that decoding needs them.

ScanPlanBuilder 🔒

Builds a ScanPlan from a decoder’s row-group frontier and the columns each decoding stage reads.

SelectedRows 🔒

Counts the selected rows before a position in a row group.

StageColumns 🔒

The decoder’s batch size and decoding stages.

StagePlan 🔒

The columns that one decoding stage of a row group reads first.

StageRanges 🔒

The merge state of one stage.

Enums

PageKind

What a PlannedRange contains.

PageSet 🔒

The data pages of a column chunk that the decoder reads, in page order.

Constants

CHUNK 🔒

The next range is the whole column chunk. The column has no offset index.

DICTIONARY 🔒

The next range is the dictionary page.

Functions

position 🔒

Converts a column or page position to a heap entry field.

Type Aliases

HeadPosition 🔒

Which range of a column chunk is next: CHUNK, DICTIONARY, or the position of a data page in the pages that the decoder reads.

HeapEntry 🔒

A heap entry: the sort key of the next range of a cursor, the position of the column in StageRanges::columns, and the HeadPosition of that range. The column position breaks ties, so ranges with equal keys stay in file order of their columns.

RangeOrder 🔒

How the heap orders the next ranges of different column chunks: by first row, then more rows first (a dictionary page), then by file offset. The ranges of one column chunk keep file order, also a page with no planned rows that the predicate cache reads.