On Thu, Jun 2, 2022 at 6:37 PM Mary Xu <yxu2...@gmail.com> wrote: > I was using an object access hook for oat_post_create access while creating > an extension and expected that I would be able to query for the newly created > extension with get_extension_oid(), but it was returning InvalidOid. However, > the same process works for triggers, so I was wondering what the expected > behavior is? > From the documentation in objectaccess.h, it doesn't mention anything about > CommandCounterIncrement() for POST_CREATE which implied to me that it wasn't > something I would need to worry about. > One option I thought of was this patch where CCI is called before the access > hook so that the new tuple is visible in the hook. Another option would be to > revise the documentation to reflect the expected behavior.
I don't think a proposal to add CommandCounterIncrement() calls just for the convenience of object access hooks has much chance of being accepted. Possibly there is some work that could be done to ensure consistent placement of the calls to post-create hooks so that either all of them happen before, or all of them happen after, a CCI has occurred, but I'm not sure whether or not that is feasible. Currently, I don't think we promise anything about whether a post-create hook call will occur before or after a CCI, which is why sepgsql_schema_post_create(), sepgsql_schema_post_create(), and sepgsql_attribute_post_create() perform a catalog scan using SnapshotSelf, while sepgsql_database_post_create() uses get_database_oid(). You might want to adopt a similar technique. -- Robert Haas EDB: http://www.enterprisedb.com
