"Vance Maverick" <vmaverick@xxxxxxx> writes: > Do I have this right? If so, the side table sounds like the right choice.... No, if the null bit is set then the field isn't stored at all. You don't pay the alignment or storage overhead at all. The only cost is for the null bitmap itself. If you have *any* null fields then you pay one bit for *every* field plus alignment to a 4-byte boundary. Except there's one available free byte so if you have 8 or fewer fields even that is entirely free. -- Gregory Stark EnterpriseDB http://www.enterprisedb.com Get trained by Bruce Momjian - ask me about EnterpriseDB's PostgreSQL training! ---------------------------(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
