On Thu, Oct 20, 2005 at 03:57:41PM +0900, Michael Glaesemann wrote: > On Oct 20, 2005, at 15:44 , Michael Fuhr wrote: > > expression IS DISTINCT FROM expression > > > > For non-null inputs this is the same as the <> operator. However, > > when both inputs are null it will return false, and when just one > > input is null it will return true. Thus it effectively acts as > > though null were a normal data value, rather than "unknown". > > Interesting! Thanks, Michael. You don't happen to know off the top of > your head if that's standard SQL, do you? IS DISTINCT FROM is defined in SQL:1999 and SQL:2003. -- Michael Fuhr ---------------------------(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