On Thu, Sep 2, 2021 at 4:48 PM Tom Lane <tgl@xxxxxxxxxxxxx> wrote: > That is pretty weird, all right. The only idea that comes to mind > immediately is that maybe that table's pkey index is corrupt and needs > to be reindexed. This isn't a great theory, because I don't see why > a corrupt index would lead to bogus unique-constraint errors rather > than missed ones. But at least it squares with the observation that > only that table is having issues. This is easy enough to check using the contrib/amcheck extension. jesusthefrog could try this, and report back what they see: CREATE EXTENSION IF NOT EXISTS amcheck SELECT bt_index_check('my_uuid_index', true); If that doesn't show any errors, then there is a chance that this will: SELECT bt_index_parent_check('my_uuid_index', true); Note that the parent variant takes a disruptive lock that will block write DML. You might prefer to just use the first query if this is running in a production environment. -- Peter Geoghegan