Hrm, yet Bruce mentions it in one of his documents. http://momjian.us/main/writings/pgsql/data_processing.pdfIt may be undocumented, but it get a lot of hits on google :)
why google? look to pgsql/src/backend/utils/adt/date.c :-) Regards Pavel Stehule ---------------------------(end of broadcast)--------------------------- TIP 9: In versions below 8.0, the planner will ignore your desire to choose an index scan if your joining column's datatypes do not match