diff options
| -rw-r--r-- | src/backend/access/heap/heapam.c | 18 |
1 files changed, 8 insertions, 10 deletions
diff --git a/src/backend/access/heap/heapam.c b/src/backend/access/heap/heapam.c index 9b5f417eac4..1585861a021 100644 --- a/src/backend/access/heap/heapam.c +++ b/src/backend/access/heap/heapam.c @@ -2044,12 +2044,10 @@ heap_prepare_insert(Relation relation, HeapTuple tup, TransactionId xid, CommandId cid, int options) { /* - * Parallel operations are required to be strictly read-only in a parallel - * worker. Parallel inserts are not safe even in the leader in the - * general case, because group locking means that heavyweight locks for - * relation extension or GIN page locks will not conflict between members - * of a lock group, but we don't prohibit that case here because there are - * useful special cases that we can safely allow, such as CREATE TABLE AS. + * To allow parallel inserts, we need to ensure that they are safe to be + * performed in workers. We have the infrastructure to allow parallel + * inserts in general except for the cases where inserts generate a new + * CommandId (eg. inserts into a table having a foreign key column). */ if (IsParallelWorker()) ereport(ERROR, @@ -5725,10 +5723,10 @@ heap_inplace_update(Relation relation, HeapTuple tuple) uint32 newlen; /* - * For now, parallel operations are required to be strictly read-only. - * Unlike a regular update, this should never create a combo CID, so it - * might be possible to relax this restriction, but not without more - * thought and testing. It's not clear that it would be useful, anyway. + * For now, we don't allow parallel updates. Unlike a regular update, + * this should never create a combo CID, so it might be possible to relax + * this restriction, but not without more thought and testing. It's not + * clear that it would be useful, anyway. */ if (IsInParallelMode()) ereport(ERROR, |