diff options
| author | Alvaro Herrera <alvherre@alvh.no-ip.org> | 2022-04-12 09:29:39 +0200 |
|---|---|---|
| committer | Alvaro Herrera <alvherre@alvh.no-ip.org> | 2022-04-12 09:29:39 +0200 |
| commit | ce4f46fdc814eb1b704d81640f6d8f03625d0f53 (patch) | |
| tree | 782a82bc2a2a811751ea053ee9793d252d296011 /src/backend/parser/parse_merge.c | |
| parent | a4b57543acfb52cc7c7e031501002563f536b929 (diff) | |
| download | postgresql-ce4f46fdc814eb1b704d81640f6d8f03625d0f53.tar.gz postgresql-ce4f46fdc814eb1b704d81640f6d8f03625d0f53.zip | |
Change mechanism to set up source targetlist in MERGE
We were setting MERGE source subplan's targetlist by expanding the
individual attributes of the source relation completely, early in the
parse analysis phase. This failed to work when the condition of an
action included a whole-row reference, causing setrefs.c to error out
with
ERROR: variable not found in subplan target lists
because at that point there is nothing to resolve the whole-row
reference with. We can fix this by having preprocess_targetlist expand
the source targetlist for Vars required from the source rel by all
actions. Moreover, by using this expansion mechanism we can do away
with the targetlist expansion in transformMergeStmt, which is good
because then we no longer pull in columns that aren't needed for
anything.
Add a test case for the problem.
While at it, remove some redundant code in preprocess_targetlist():
MERGE was doing separately what is already being done for UPDATE/DELETE,
so we can just rely on the latter and remove the former. (The handling
of inherited rels was different for MERGE, but that was a no-longer-
necessary hack.)
Fix outdated, related comments for fix_join_expr also.
Author: Richard Guo <guofenglinux@gmail.com>
Author: Álvaro Herrera <alvherre@alvh.no-ip.org>
Reported-by: Joe Wildish <joe@lateraljoin.com>
Discussion: https://postgr.es/m/fab3b90a-914d-46a9-beb0-df011ee39ee5@www.fastmail.com
Diffstat (limited to 'src/backend/parser/parse_merge.c')
| -rw-r--r-- | src/backend/parser/parse_merge.c | 9 |
1 files changed, 5 insertions, 4 deletions
diff --git a/src/backend/parser/parse_merge.c b/src/backend/parser/parse_merge.c index 5d0035a12b6..bb9d76306b7 100644 --- a/src/backend/parser/parse_merge.c +++ b/src/backend/parser/parse_merge.c @@ -18,7 +18,6 @@ #include "access/sysattr.h" #include "miscadmin.h" #include "nodes/makefuncs.h" -#include "nodes/nodeFuncs.h" #include "parser/analyze.h" #include "parser/parse_collate.h" #include "parser/parsetree.h" @@ -205,9 +204,11 @@ transformMergeStmt(ParseState *pstate, MergeStmt *stmt) pstate->p_target_nsitem->p_names->aliasname), errdetail("The name is used both as MERGE target table and data source.")); - qry->targetList = expandNSItemAttrs(pstate, nsitem, 0, false, - exprLocation(stmt->sourceRelation)); - + /* + * There's no need for a targetlist here; it'll be set up by + * preprocess_targetlist later. + */ + qry->targetList = NIL; qry->rtable = pstate->p_rtable; /* |