Reconsider the handling of procedure OUT parameters

Enterprise / PostgreSQL - Tom Lane [sss.pgh.pa.us] - 10 June 2021 21:11 UTC

Commit 2453ea142 redefined pg_proc.proargtypes to include the types of OUT parameters, for procedures only. While that had some advantages for implementing the SQL-spec behavior of DROP PROCEDURE, it was pretty disastrous from a number of other perspectives. Notably, since the primary key of pg_proc is name + proargtypes, this made it possible to have multiple procedures with identical names + input arguments and differing output argument types. That would make it impossible to call any one of the procedures by writing just NULL (or "?", or any other data-type-free notation) for the output argument(s). The change also seems likely to cause grave confusion for client applications that examine pg_proc and expect the traditional definition of proargtypes.

Hence, revert the definition of proargtypes to what it was, and undo a number of complications that had been added to support that.

To support the SQL-spec behavior of DROP PROCEDURE, when there are no argmode markers in the command's parameter list, we perform the lookup both ways (that is, matching against both proargtypes and proallargtypes), succeeding if we get just one unique match. In principle this could result in ambiguous-function failures that would not happen when using only one of the two rules. However, overloading of procedure names is thought to be a pretty rare usage, so this shouldn't cause many problems in practice. Postgres-specific code such as pg_dump can defend against any possibility of such failures by being careful to specify argmodes for all procedure arguments.

This also fixes a few other bugs in the area of CALL statements with named parameters, and improves the documentation a little.

catversion bump forced because the representation of procedures with OUT arguments changes.

Discussion: https://postgr.es/m/3742981.1621533210@sss.pgh.pa.us

e56bce5d43 Reconsider the handling of procedure OUT parameters.
doc/src/sgml/catalogs.sgml | 5 +-
doc/src/sgml/plpgsql.sgml | 17 +-
doc/src/sgml/ref/alter_extension.sgml | 11 +-
doc/src/sgml/ref/alter_procedure.sgml | 4 +-
doc/src/sgml/ref/call.sgml | 26 +++-
doc/src/sgml/ref/comment.sgml | 11 +-
doc/src/sgml/ref/drop_procedure.sgml | 92 +++++++++--
doc/src/sgml/ref/drop_routine.sgml | 42 ++++-
doc/src/sgml/ref/security_label.sgml | 11 +-
doc/src/sgml/xfunc.sgml | 22 +--
src/backend/catalog/namespace.c | 68 ++++++--
src/backend/catalog/pg_aggregate.c | 2 +-
src/backend/catalog/pg_proc.c | 6 +-
src/backend/commands/functioncmds.c | 137 ++++++++--------
src/backend/executor/functions.c | 36 +----
src/backend/nodes/copyfuncs.c | 2 +
src/backend/nodes/equalfuncs.c | 2 +
src/backend/optimizer/util/clauses.c | 89 ++++++++---
src/backend/parser/analyze.c | 92 ++++++++++-
src/backend/parser/gram.y | 109 +++++--------
src/backend/parser/parse_func.c | 207 +++++++++++++++++++------
src/backend/parser/parse_oper.c | 4 +-
src/backend/utils/adt/regproc.c | 11 +-
src/backend/utils/adt/ruleutils.c | 12 +-
src/backend/utils/fmgr/funcapi.c | 4 +-
src/bin/pg_dump/t/002_pg_dump.pl | 2 +-
src/include/catalog/catversion.h | 2 +-
src/include/catalog/namespace.h | 2 +
src/include/catalog/pg_proc.h | 2 +-
src/include/funcapi.h | 3 +-
src/include/nodes/parsenodes.h | 37 +++--
src/include/optimizer/optimizer.h | 3 +-
src/include/parser/parse_func.h | 1 +
src/pl/plpgsql/src/expected/plpgsql_call.out | 76 +++++++++
src/pl/plpgsql/src/pl_comp.c | 1 -
src/pl/plpgsql/src/pl_exec.c | 36 ++---
src/pl/plpgsql/src/sql/plpgsql_call.sql | 64 ++++++++
src/pl/plpython/expected/plpython_call.out | 4 +-
src/pl/plpython/plpy_procedure.c | 4 +-
src/pl/plpython/sql/plpython_call.sql | 2 +-
src/pl/tcl/expected/pltcl_call.out | 4 +-
src/pl/tcl/sql/pltcl_call.sql | 2 +-
src/test/regress/expected/create_procedure.out | 149 +++++++++++++++---
src/test/regress/sql/create_procedure.sql | 45 +++++-
44 files changed, 1069 insertions(+), 392 deletions(-)

Upstream: git.postgresql.org


  • Share