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| author | Tom Lane <tgl@sss.pgh.pa.us> | 2009-04-05 22:28:59 +0000 |
|---|---|---|
| committer | Tom Lane <tgl@sss.pgh.pa.us> | 2009-04-05 22:28:59 +0000 |
| commit | f2110a757d0bdca766fa1b8562c7dcb1a53fd422 (patch) | |
| tree | 5f3dbadfee7aa7ac8affae27881666add9e527b3 /src/backend/utils/adt/arrayfuncs.c | |
| parent | eb4c723e562c350f3af828ebe0e8847c79a02a69 (diff) | |
| download | postgresql-f2110a757d0bdca766fa1b8562c7dcb1a53fd422.tar.gz postgresql-f2110a757d0bdca766fa1b8562c7dcb1a53fd422.zip | |
Change cardinality() into a C-code function, instead of a SQL-language
alias for array_length(v,1). The efficiency gain here is doubtless
negligible --- what I'm interested in is making sure that if we have
second thoughts about the definition, we will not have to force a
post-beta initdb to change the implementation.
Diffstat (limited to 'src/backend/utils/adt/arrayfuncs.c')
| -rw-r--r-- | src/backend/utils/adt/arrayfuncs.c | 24 |
1 files changed, 23 insertions, 1 deletions
diff --git a/src/backend/utils/adt/arrayfuncs.c b/src/backend/utils/adt/arrayfuncs.c index 111d6b8c263..8b36edc42fa 100644 --- a/src/backend/utils/adt/arrayfuncs.c +++ b/src/backend/utils/adt/arrayfuncs.c @@ -8,7 +8,7 @@ * * * IDENTIFICATION - * $PostgreSQL: pgsql/src/backend/utils/adt/arrayfuncs.c,v 1.153 2009/01/30 21:21:18 tgl Exp $ + * $PostgreSQL: pgsql/src/backend/utils/adt/arrayfuncs.c,v 1.154 2009/04/05 22:28:59 tgl Exp $ * *------------------------------------------------------------------------- */ @@ -1669,6 +1669,28 @@ array_length(PG_FUNCTION_ARGS) } /* + * array_cardinality : + * SQL-spec alias for array_length(v, 1) + */ +Datum +array_cardinality(PG_FUNCTION_ARGS) +{ + ArrayType *v = PG_GETARG_ARRAYTYPE_P(0); + int *dimv; + int result; + + /* Sanity check: does it look like an array at all? */ + if (ARR_NDIM(v) <= 0 || ARR_NDIM(v) > MAXDIM) + PG_RETURN_NULL(); + + dimv = ARR_DIMS(v); + + result = dimv[0]; + + PG_RETURN_INT32(result); +} + +/* * array_ref : * This routine takes an array pointer and a subscript array and returns * the referenced item as a Datum. Note that for a pass-by-reference |