diff options
| author | Dean Rasheed | 2023-09-30 09:52:21 +0000 |
|---|---|---|
| committer | Dean Rasheed | 2023-09-30 09:52:21 +0000 |
| commit | 1d5caec221d85b8950a1ee3d8bb6fad262549ea6 (patch) | |
| tree | dbb0d619c692ab169ee97932ace3cad690950e5f /src/include | |
| parent | f02154652d1a83d80f4bee93b58ecdbd8c33378b (diff) | |
Fix EvalPlanQual rechecking during MERGE.
Under some circumstances, concurrent MERGE operations could lead to
inconsistent results, that varied according the plan chosen. This was
caused by a lack of rowmarks on the source relation, which meant that
EvalPlanQual rechecking was not guaranteed to return the same source
tuples when re-running the join query.
Fix by ensuring that preprocess_rowmarks() sets up PlanRowMarks for
all non-target relations used in MERGE, in the same way that it does
for UPDATE and DELETE.
Per bug #18103. Back-patch to v15, where MERGE was introduced.
Dean Rasheed, reviewed by Richard Guo.
Discussion: https://postgr.es/m/18103-c4386baab8e355e3%40postgresql.org
Diffstat (limited to 'src/include')
| -rw-r--r-- | src/include/nodes/execnodes.h | 4 | ||||
| -rw-r--r-- | src/include/nodes/plannodes.h | 4 |
2 files changed, 4 insertions, 4 deletions
diff --git a/src/include/nodes/execnodes.h b/src/include/nodes/execnodes.h index cb714f4a196..869465d6f80 100644 --- a/src/include/nodes/execnodes.h +++ b/src/include/nodes/execnodes.h @@ -721,8 +721,8 @@ typedef struct EState * ExecRowMark - * runtime representation of FOR [KEY] UPDATE/SHARE clauses * - * When doing UPDATE, DELETE, or SELECT FOR [KEY] UPDATE/SHARE, we will have an - * ExecRowMark for each non-target relation in the query (except inheritance + * When doing UPDATE/DELETE/MERGE/SELECT FOR [KEY] UPDATE/SHARE, we will have + * an ExecRowMark for each non-target relation in the query (except inheritance * parent RTEs, which can be ignored at runtime). Virtual relations such as * subqueries-in-FROM will have an ExecRowMark with relation == NULL. See * PlanRowMark for details about most of the fields. In addition to fields diff --git a/src/include/nodes/plannodes.h b/src/include/nodes/plannodes.h index 1b787fe0318..8cafbf3f8a4 100644 --- a/src/include/nodes/plannodes.h +++ b/src/include/nodes/plannodes.h @@ -1309,7 +1309,7 @@ typedef struct Limit * doing a separate remote query to lock each selected row is usually pretty * unappealing, so early locking remains a credible design choice for FDWs. * - * When doing UPDATE, DELETE, or SELECT FOR UPDATE/SHARE, we have to uniquely + * When doing UPDATE/DELETE/MERGE/SELECT FOR UPDATE/SHARE, we have to uniquely * identify all the source rows, not only those from the target relations, so * that we can perform EvalPlanQual rechecking at need. For plain tables we * can just fetch the TID, much as for a target relation; this case is @@ -1338,7 +1338,7 @@ typedef enum RowMarkType * PlanRowMark - * plan-time representation of FOR [KEY] UPDATE/SHARE clauses * - * When doing UPDATE, DELETE, or SELECT FOR UPDATE/SHARE, we create a separate + * When doing UPDATE/DELETE/MERGE/SELECT FOR UPDATE/SHARE, we create a separate * PlanRowMark node for each non-target relation in the query. Relations that * are not specified as FOR UPDATE/SHARE are marked ROW_MARK_REFERENCE (if * regular tables or supported foreign tables) or ROW_MARK_COPY (if not). |