On Tue, Sep 10, 2024 at 3:05 PM Noah Misch <n...@leadboat.com> wrote: > > On Tue, Sep 10, 2024 at 05:56:47PM -0400, Tom Lane wrote: > > Masahiko Sawada <sawada.m...@gmail.com> writes: > > > On Tue, Sep 10, 2024 at 11:57 AM Tom Lane <t...@sss.pgh.pa.us> wrote: > > >> Yeah, that seems like it could work. But are we sure that replicas > > >> get a copy of the primary's control file rather than creating their > > >> own? > > > > > Yes, I think so. Since at least the system identifiers of primary and > > > replicas must be identical for physical replication, if replicas use > > > their own control files then they cannot start the replication. > > > > Got it. So now I'm wondering if we need all the complexity of storing > > stuff in the GIN metapages. Could we simply read the (primary's) > > signedness out of pg_control and use that? > > Yes.
Indeed. I've attached a PoC patch for this idea. We write the default char signedness to the control file at initdb time. Then when comparing two trgms, pg_trgm opclasses use a comparison function based on the char signedness of the cluster. I've confirmed that the patch fixes the reported case at least. Regards, -- Masahiko Sawada Amazon Web Services: https://aws.amazon.com
poc_char_signedness.patch
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