[EMAIL PROTECTED] (Dave Cramer) wrote:
> It appears that the optimizer only uses indexes for = clause? 

It can use indices only if there is a given prefix.

Thus:
   where text_field like 'A%'

can use the index, essentially transforming this into the clauses

   where text_field >= 'A' and
         text_field < 'B'.

You can't get much out of an index for
   where text_field like '%SOMETHING'
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