<...snip...>
>
> I'd try a functional index first. If that didn't do the job, I'd use a
> trigger-maintained column _purely_ as an optimisation (ie I could drop
> it and lose no data) that stored text representations of the data.
> Honestly, though, I expect the functional index would be more than good
> enough and probably wouldn't have much of an INSERT/UPDATE cost.
<.../snip...>
I made a test table and tried a functional index (coalescing the two
columns). Works!
Now let me try that on a mirror on my full real table with millions of
rows and report back. Sounds like a cleaner design so I may be on to
something!
Hope this helps the original poster with some ideas too.