On Tue, Jan 17, 2006 at 12:57:30 -0800, George Pavlov <[EMAIL PROTECTED]> wrote: > I have a table of names with two subsets of entities. I want to find > those names from set 1 that are substrings of names from set 2 from the > same table. Basically the pared down query I want is something like > this: > > select t1.myname, t2.myname > from mytable t1 > inner join mytable t2 > on position (t1.myname in t2.myname) > 0 > where t1.flag = 1 > and t2.flag = 2 > ; > > I have gone through a few variations on the theme, but none perform too > well. Any advice on the best way to optimize a query like this would be > appreciated.
I wouldn't expect this to be fast. You would need some sort of index on which substrings are in which names in table 2 to be able to use an index scan. You could build a table for this, but this might be worse for you than what you are doing now. ---------------------------(end of broadcast)--------------------------- TIP 6: explain analyze is your friend
