Hi! This limitation applies not only to wide tables - it also applies to tables where TOASTed values are updated very often. You would soon be out of available TOAST value ID because in case of high frequency updates autovacuum cleanup rate won't keep up with the updates. It is discussed in [1].
On Fri, Apr 21, 2023 at 9:39 AM Jakub Wartak <jakub.war...@enterprisedb.com> wrote: > Hi -hackers, > > I would like to ask if it wouldn't be good idea to copy the > https://wiki.postgresql.org/wiki/TOAST#Total_table_size_limit > discussion (out-of-line OID usage per TOAST-ed columns / potential > limitation) to the official "Appendix K. PostgreSQL Limits" with also > little bonus mentioning the "still searching for an unused OID in > relation" notice. Although it is pretty obvious information for some > and from commit 7fbcee1b2d5f1012c67942126881bd492e95077e and the > discussion in [1], I wonder if the information shouldn't be a little > more well known via the limitation (especially to steer people away > from designing very wide non-partitioned tables). > > Regards, > -J. > > [1] - > https://www.postgresql.org/message-id/flat/16722-93043fb459a41073%40postgresql.org > > > [1] https://www.postgresql.org/message-id/CAN-LCVPRvRzxeUdYdDCZ7UwZQs1NmZpqBUCd%3D%2BRdMPFTyt-bRQ%40mail.gmail.com -- Regards, Nikita Malakhov Postgres Professional The Russian Postgres Company https://postgrespro.ru/