Manuel Sugawara <masm@fciencias.unam.mx> writes: > Using the second plan the query is returning tuples where > a=F1o_semestre <> 20071
You seem to have worse problems than that, because as given the insc_registra_grupo function never returns non-NULL, and so the query ought not be returning any tuples at all. I suspect pilot error --- perhaps looking at the wrong schema or some such? regards, tom lane ---------------------------(end of broadcast)--------------------------- TIP 4: Have you searched our list archives? http://archives.postgresql.org