mirror of
https://github.com/zebrajr/postgres.git
synced 2025-12-07 12:20:31 +01:00
a54faa6591
Historically, we've allowed users to add a CHECK constraint to a child table and then add an identical CHECK constraint to the parent. This results in "merging" the two constraints so that the pre-existing child constraint ends up with both conislocal = true and coninhcount > 0. However, if you tried to do it in the other order, you got a duplicate constraint error. This is problematic for pg_dump, which needs to issue separated ADD CONSTRAINT commands in some cases, but has no good way to ensure that the constraints will be added in the required order. And it's more than a bit arbitrary, too. The goal of complaining about duplicated ADD CONSTRAINT commands can be served if we reject the case of adding a constraint when the existing one already has conislocal = true; but if it has conislocal = false, let's just make the ADD CONSTRAINT set conislocal = true. In this way, either order of adding the constraints has the same end result. Another problem was that the code allowed creation of a parent constraint marked convalidated that is merged with a child constraint that is !convalidated. In this case, an inheritance scan of the parent table could emit some rows violating the constraint condition, which would be an unexpected result given the marking of the parent constraint as validated. Hence, forbid merging of constraints in this case. (Note: valid child and not-valid parent seems fine, so continue to allow that.) Per report from Benedikt Grundmann. Back-patch to 9.2 where we introduced possibly-not-valid check constraints. The second bug obviously doesn't apply before that, and I think the first doesn't either, because pg_dump only gets into this situation when dealing with not-valid constraints. Report: <CADbMkNPT-Jz5PRSQ4RbUASYAjocV_KHUWapR%2Bg8fNvhUAyRpxA%40mail.gmail.com> Discussion: <22108.1475874586@sss.pgh.pa.us> |
||
|---|---|---|
| .. | ||
| aggregatecmds.c | ||
| alter.c | ||
| analyze.c | ||
| async.c | ||
| cluster.c | ||
| collationcmds.c | ||
| comment.c | ||
| constraint.c | ||
| conversioncmds.c | ||
| copy.c | ||
| createas.c | ||
| dbcommands.c | ||
| define.c | ||
| discard.c | ||
| dropcmds.c | ||
| explain.c | ||
| extension.c | ||
| foreigncmds.c | ||
| functioncmds.c | ||
| indexcmds.c | ||
| lockcmds.c | ||
| Makefile | ||
| opclasscmds.c | ||
| operatorcmds.c | ||
| portalcmds.c | ||
| prepare.c | ||
| proclang.c | ||
| schemacmds.c | ||
| seclabel.c | ||
| sequence.c | ||
| tablecmds.c | ||
| tablespace.c | ||
| trigger.c | ||
| tsearchcmds.c | ||
| typecmds.c | ||
| user.c | ||
| vacuum.c | ||
| vacuumlazy.c | ||
| variable.c | ||
| view.c | ||