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| author | Tom Lane <tgl@sss.pgh.pa.us> | 2008-10-31 19:37:56 +0000 |
|---|---|---|
| committer | Tom Lane <tgl@sss.pgh.pa.us> | 2008-10-31 19:37:56 +0000 |
| commit | 9b46abb7c47de8aa408a8c83666fd67c5447eb85 (patch) | |
| tree | 034991f27008de03ff71f505431b10a1b2ae5e5e /src/backend/utils/fmgr | |
| parent | cd97f98844b5640b1cdc701c691c962155dce3b4 (diff) | |
| download | postgresql-9b46abb7c47de8aa408a8c83666fd67c5447eb85.tar.gz | |
Allow SQL-language functions to return the output of an INSERT/UPDATE/DELETE
RETURNING clause, not just a SELECT as formerly.
A side effect of this patch is that when a set-returning SQL function is used
in a FROM clause, performance is improved because the output is collected into
a tuplestore within the function, rather than using the less efficient
value-per-call mechanism.
Diffstat (limited to 'src/backend/utils/fmgr')
| -rw-r--r-- | src/backend/utils/fmgr/README | 6 |
1 files changed, 4 insertions, 2 deletions
diff --git a/src/backend/utils/fmgr/README b/src/backend/utils/fmgr/README index 7c1ccc5bf8..c2624ee475 100644 --- a/src/backend/utils/fmgr/README +++ b/src/backend/utils/fmgr/README @@ -1,4 +1,4 @@ -$PostgreSQL: pgsql/src/backend/utils/fmgr/README,v 1.15 2008/10/29 00:00:38 tgl Exp $ +$PostgreSQL: pgsql/src/backend/utils/fmgr/README,v 1.16 2008/10/31 19:37:56 tgl Exp $ Function Manager ================ @@ -434,7 +434,9 @@ and returns null. isDone is not used and should be left at ExprSingleResult. The Tuplestore must be created with randomAccess = true if SFRM_Materialize_Random is set in allowedModes, but it can (and preferably -should) be created with randomAccess = false if not. +should) be created with randomAccess = false if not. Callers that can support +both ValuePerCall and Materialize mode will set SFRM_Materialize_Preferred, +or not, depending on which mode they prefer. If available, the expected tuple descriptor is passed in ReturnSetInfo; in other contexts the expectedDesc field will be NULL. The function need |