pgsql: Fix race condition in statext_store().

2020-03-31 Thread Tom Lane
Fix race condition in statext_store(). Must hold some lock on the pg_statistic_ext_data catalog *before* we look up the tuple we aim to replace. Otherwise a concurrent VACUUM FULL or similar operation could move it to a different TID, leaving us trying to replace the wrong tuple. Back-patch to v

pgsql: Fix race condition in statext_store().

2020-03-31 Thread Tom Lane
Fix race condition in statext_store(). Must hold some lock on the pg_statistic_ext_data catalog *before* we look up the tuple we aim to replace. Otherwise a concurrent VACUUM FULL or similar operation could move it to a different TID, leaving us trying to replace the wrong tuple. Back-patch to v