This is just to report success: I dropped all indices and repeated: UPDATE intwfs SET id = nextval('myseq'); and it worked fine - took 3681 secs (my estimate of an hour wasn't far out). Now doing a VACUUM FULL to remove the old tuples. -- Clive Page Dept of Physics & Astronomy, University of Leicester, Tel +44 116 252 3551 Leicester, LE1 7RH, U.K. Fax +44 116 252 3311 ---------------------------(end of broadcast)--------------------------- TIP 9: the planner will ignore your desire to choose an index scan if your joining column's datatypes do not match