On Thu, Oct 17, 2024 at 9:59 AM Shayon Mukherjee <shay...@gmail.com> wrote: > My take away from whether or not an in-place update is needed on pg_index [1] > > - It’s unclear to me why it’s needed. > - I understand the xmin would get incremented when using CatalogTupleUpdate > to update indisenabled. > - However, I haven’t been able to replicate any odd behavior locally or CI. > - FWIW - REINDEX CONCURRENTLY (via index_swap), index_constraint_create and > few other places perform CatalogTupleUpdate to update the relevant attributes > as well. > > Based on the above summary and after my testing I would like to propose a v3 > of the patch. The only difference between this and v1 [2] is that the update > of pg_index row happens via CatalogTupleUpdate. > > [1] > https://www.postgresql.org/message-id/20180618215635.m5vrnxdxhxytv...@alap3.anarazel.de > [2] > https://www.postgresql.org/message-id/EF2313B8-A017-4869-9B7F-A24EDD8795DE%40gmail.com
In-place updates are generally bad news, so I think this patch shouldn't use them. However, someone will need to investigate whether that breaks the indcheckxmin thing that Andres mentions in your [1], and if it does, figure out what to do about it. Creating a test case to show the breakage would probably be a good first step, to frame the discussion. -- Robert Haas EDB: http://www.enterprisedb.com
