Hi, On 2018-07-23 21:03:32 +0300, Mariel Cherkassky wrote: > Today I faced a situation where I saw a postgresql 9.2 database that had > duplicated rows in pg_autid. I saw 6 roles while 3 of them were duplicated > (3 uniques rolenames in total). I checked and the oid of the duplicates > were the same oid as the originals. The solution was running vacuum on the > table but I wanted to understand how this situation was created ? Why even > with unique index on the rolname I saw duplicated values for rolname ? That suggests some form of corruption. Which version of 9.2 did this occur on? Did you have any OS level crashes? Ran with fsync=off? Please note that 9.2 is not supported anymore. Greetings, Andres Freund
