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| author | Teodor Sigaev <teodor@sigaev.ru> | 2018-04-03 19:46:45 +0300 |
|---|---|---|
| committer | Teodor Sigaev <teodor@sigaev.ru> | 2018-04-03 19:46:45 +0300 |
| commit | 710d90da1fd8c1d028215ecaf7402062079e99e9 (patch) | |
| tree | 6fb5d284edb7a9c37e3ae633c92779a65d1b97c6 /src/backend/utils/adt/selfuncs.c | |
| parent | 4ab299981576ca0f3dbb879b5e2b704e743d87f3 (diff) | |
| download | postgresql-710d90da1fd8c1d028215ecaf7402062079e99e9.tar.gz postgresql-710d90da1fd8c1d028215ecaf7402062079e99e9.zip | |
Add prefix operator for TEXT type.
The prefix operator along with SP-GiST indexes can be used as an alternative
for LIKE 'word%' commands and it doesn't have a limitation of string/prefix
length as B-Tree has.
Bump catalog version
Author: Ildus Kurbangaliev with some editorization by me
Review by: Arthur Zakirov, Alexander Korotkov, and me
Discussion: https://www.postgresql.org/message-id/flat/20180202180327.222b04b3@wp.localdomain
Diffstat (limited to 'src/backend/utils/adt/selfuncs.c')
| -rw-r--r-- | src/backend/utils/adt/selfuncs.c | 33 |
1 files changed, 33 insertions, 0 deletions
diff --git a/src/backend/utils/adt/selfuncs.c b/src/backend/utils/adt/selfuncs.c index bf240aa9c5a..f998d859c1c 100644 --- a/src/backend/utils/adt/selfuncs.c +++ b/src/backend/utils/adt/selfuncs.c @@ -1488,6 +1488,16 @@ likesel(PG_FUNCTION_ARGS) } /* + * prefixsel - selectivity of prefix operator + */ +Datum +prefixsel(PG_FUNCTION_ARGS) +{ + PG_RETURN_FLOAT8(patternsel(fcinfo, Pattern_Type_Prefix, false)); +} + +/* + * * iclikesel - Selectivity of ILIKE pattern match. */ Datum @@ -2907,6 +2917,15 @@ likejoinsel(PG_FUNCTION_ARGS) } /* + * prefixjoinsel - Join selectivity of prefix operator + */ +Datum +prefixjoinsel(PG_FUNCTION_ARGS) +{ + PG_RETURN_FLOAT8(patternjoinsel(fcinfo, Pattern_Type_Prefix, false)); +} + +/* * iclikejoinsel - Join selectivity of ILIKE pattern match. */ Datum @@ -5947,6 +5966,20 @@ pattern_fixed_prefix(Const *patt, Pattern_Type ptype, Oid collation, result = regex_fixed_prefix(patt, true, collation, prefix, rest_selec); break; + case Pattern_Type_Prefix: + /* Prefix type work is trivial. */ + result = Pattern_Prefix_Partial; + *rest_selec = 1.0; /* all */ + *prefix = makeConst(patt->consttype, + patt->consttypmod, + patt->constcollid, + patt->constlen, + datumCopy(patt->constvalue, + patt->constbyval, + patt->constlen), + patt->constisnull, + patt->constbyval); + break; default: elog(ERROR, "unrecognized ptype: %d", (int) ptype); result = Pattern_Prefix_None; /* keep compiler quiet */ |