Torsten Förtsch wrote: > assuming > > SELECT nextval('s'), currval('s'); > > or > > SELECT * FROM (VALUES (nextval('s'), currval('s'))) t; > > is there any guarantee that the 2 output values are the same? You can use at EXPLAIN (VERBOSE) output to see if it will work in this special case, but I wouldn't depend on it in general. Yours, Laurenz Albe -- Cybertec | https://www.cybertec-postgresql.com