postgresql/src/include/nodes/multibitmapset.h

40 lines
1.6 KiB
C

/*-------------------------------------------------------------------------
*
* multibitmapset.h
* Lists of Bitmapsets
*
* A multibitmapset is useful in situations where members of a set can
* be identified by two small integers; for example, varno and varattno
* of a group of Vars within a query. The implementation is a List of
* Bitmapsets, so that the empty set can be represented by NIL. (But,
* as with Bitmapsets, that's not the only allowed representation.)
* The zero-based index of a List element is the first identifying value,
* and the (also zero-based) index of a bit within that Bitmapset is
* the second identifying value. There is no expectation that the
* Bitmapsets should all be the same size.
*
* The available operations on multibitmapsets are intended to parallel
* those on bitmapsets, for example union and intersection. So far only
* a small fraction of that has been built out; we'll add more as needed.
*
*
* Copyright (c) 2022-2023, PostgreSQL Global Development Group
*
* src/include/nodes/multibitmapset.h
*
*-------------------------------------------------------------------------
*/
#ifndef MULTIBITMAPSET_H
#define MULTIBITMAPSET_H
#include "nodes/bitmapset.h"
#include "nodes/pg_list.h"
extern List *mbms_add_member(List *a, int listidx, int bitidx);
extern List *mbms_add_members(List *a, const List *b);
extern List *mbms_int_members(List *a, const List *b);
extern bool mbms_is_member(int listidx, int bitidx, const List *a);
extern Bitmapset *mbms_overlap_sets(const List *a, const List *b);
#endif /* MULTIBITMAPSET_H */