Fix plpgsql's handling of simple expressions in scrollable cursors.
exec_save_simple_expr did not account for the possibility that
standard_planner would stick a Materialize node atop the plan
of even a simple Result, if CURSOR_OPT_SCROLL is set. This led
to an "unexpected plan node type" error.
This is a very old bug, but it'd only be reached by declaring a
cursor for a "SELECT simple-expression" query and explicitly
marking it scrollable, which is an odd thing to do. So the lack
of prior reports isn't too surprising.
Bug: #18859
Reported-by: Olleg Samoylov <splarv@ya.ru>
Author: Andrei Lepikhov <lepihov@gmail.com>
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/18859-0d5f28ac99a37059@postgresql.org
Backpatch-through: 13
Branch
------
REL_17_STABLE
Details
-------
https://git.postgresql.org/pg/commitdiff/1353b1161a790e64507428e33cc0c5975f26474b
Modified Files
--------------
src/pl/plpgsql/src/expected/plpgsql_simple.out | 11 +++++++++++
src/pl/plpgsql/src/pl_exec.c | 12 +++++++-----
src/pl/plpgsql/src/sql/plpgsql_simple.sql | 12 ++++++++++++
3 files changed, 30 insertions(+), 5 deletions(-)