bricklen <bricklen@xxxxxxxxx> writes: > We recently experienced a hard crash of a dev server due to lack of > resources (we think, still investigating). > That resulted in an interesting scenario where one of the tables was > returning 12 rows from "select * from tbl", but "select * from tbl order by > <pk column>" was only returning 11. > Looking at pg_class.reltuples, it could be clearly seen that the table in > question had a value of 12, but the primary key had only 11. > My system catalog ignorance is probably showing, but I assumed that the > table and PK pg_class.reltuples values should always be the same? I wouldn't assume that --- they're only approximations, anyway. In particular there's some moving-average behavior in there that might prevent small errors in the value from ever going away completely. > The initial observations were made by a developer: > 1). After an ANALYZE, PK reltuples remained at 11. > 2). After REINDEX, PK reltuples was still 11. > 3). After VACUUM FULL, PK reltuples was reset to 12. (2) is a bit surprising, but I'm not sure that REINDEX recomputes the reltuples value for the index. regards, tom lane -- Sent via pgsql-general mailing list (pgsql-general@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-general
