On 11/09/2007, Phoenix Kiula <[EMAIL PROTECTED]> wrote: > > The suggestion in this thread that a regex index will come into play > only when the WHERE condition specifically mentions it was indeed the > key for me.
Ok, I've hit a snag about this index. I think it's to do with how my regex is structured. Basically this column can have either IP addresses, or alphanumeric user IDs. If it is not an IP address, it is a registered user ID. What is the best way of ascertaining that a column value is *not* an IP address? I tried this: select * from trader where trader_id !~ '[0-9]+\.[0-9]+\.[0-9]+\.'; And this works, but I wonder if a partial index on a negative condition ("!~") will be slower than a positive condition? ---------------------------(end of broadcast)--------------------------- TIP 3: Have you checked our extensive FAQ? http://www.postgresql.org/docs/faq