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352a24a1f9
Gen_fmgrtab.pl creates a new file fmgrprotos.h, which contains prototypes for all functions registered in pg_proc.h. This avoids having to manually maintain these prototypes across a random variety of header files. It also automatically enforces a correct function signature, and since there are warnings about missing prototypes, it will detect functions that are defined but not registered in pg_proc.h (or otherwise used). Reviewed-by: Pavel Stehule <pavel.stehule@gmail.com>
97 lines
2.3 KiB
C
97 lines
2.3 KiB
C
/*-------------------------------------------------------------------------
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*
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* geo_selfuncs.c
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* Selectivity routines registered in the operator catalog in the
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* "oprrest" and "oprjoin" attributes.
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*
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* Portions Copyright (c) 1996-2017, PostgreSQL Global Development Group
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* Portions Copyright (c) 1994, Regents of the University of California
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*
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*
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* IDENTIFICATION
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* src/backend/utils/adt/geo_selfuncs.c
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*
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* XXX These are totally bogus. Perhaps someone will make them do
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* something reasonable, someday.
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*
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*-------------------------------------------------------------------------
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*/
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#include "postgres.h"
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#include "utils/builtins.h"
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#include "utils/geo_decls.h"
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/*
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* Selectivity functions for geometric operators. These are bogus -- unless
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* we know the actual key distribution in the index, we can't make a good
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* prediction of the selectivity of these operators.
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*
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* Note: the values used here may look unreasonably small. Perhaps they
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* are. For now, we want to make sure that the optimizer will make use
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* of a geometric index if one is available, so the selectivity had better
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* be fairly small.
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*
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* In general, GiST needs to search multiple subtrees in order to guarantee
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* that all occurrences of the same key have been found. Because of this,
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* the estimated cost for scanning the index ought to be higher than the
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* output selectivity would indicate. gistcostestimate(), over in selfuncs.c,
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* ought to be adjusted accordingly --- but until we can generate somewhat
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* realistic numbers here, it hardly matters...
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*/
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/*
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* Selectivity for operators that depend on area, such as "overlap".
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*/
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Datum
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areasel(PG_FUNCTION_ARGS)
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{
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PG_RETURN_FLOAT8(0.005);
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}
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Datum
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areajoinsel(PG_FUNCTION_ARGS)
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{
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PG_RETURN_FLOAT8(0.005);
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}
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/*
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* positionsel
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*
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* How likely is a box to be strictly left of (right of, above, below)
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* a given box?
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*/
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Datum
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positionsel(PG_FUNCTION_ARGS)
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{
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PG_RETURN_FLOAT8(0.1);
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}
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Datum
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positionjoinsel(PG_FUNCTION_ARGS)
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{
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PG_RETURN_FLOAT8(0.1);
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}
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/*
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* contsel -- How likely is a box to contain (be contained by) a given box?
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*
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* This is a tighter constraint than "overlap", so produce a smaller
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* estimate than areasel does.
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*/
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Datum
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contsel(PG_FUNCTION_ARGS)
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{
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PG_RETURN_FLOAT8(0.001);
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}
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Datum
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contjoinsel(PG_FUNCTION_ARGS)
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{
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PG_RETURN_FLOAT8(0.001);
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}
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