Re: Optimizer of Online 7.22 selects wrong index

Posted in 1997

Art S. Kagel — Fri, 01 Aug 1997 12:49:01 -0400 — source: Informix-list mailing list archive (1991-1998)

Helmut: I noticed Jason Harris' posting and this is the first time I saw your Index definitions. They had been deleted from the original posted response that I replied to. Based on the large number of indexes with the same first or first two columns the problem you are seeing is exactly what I described. If updating stats to HIGH on the columns that differentiate the indexes (st_snr, st_zeichnr, st_tnr, st_stufe, st_matnr, st_lnr) does not help; you will have to DROP DISTRIBUTIONS to get 5.0x style optimizer behavior. Please let us all know if this has helped and what the final solution was. Art S. Kagel