Quoting Jack Mills <millsjack14@...>:

<SNIP>

> The update statement is "update disc set area_code = ltrim(area_code)"
> The returned Plan "PLAN (DISC NATURAL)"
>

<SNIP>

I am not sure from your thread if you are only having an issue with
this one update. Or if you have a problem with all updates on this
database and this is just a simple example.

If it is just this update, how about if you do the following instead:

update disc set area_code = ltrim(area_code) WHERE AREA_CODE < '0';

and get a return of PLAN (DISC INDEX (DISC_IDX1))

You could also add the LTRIM to the Trigger and only have to do the
update once.
Then the performance would not be an issue.