Re: Easy question

Bert wrote:
> No i didn't defined any indexes for the table, I know the performance
> will increase with an index, but this was not my question. My question
> furthermore belongs to the access mode of the SQL statement.
> Furthermore i do not understand why the Upper function should increase
> the performance.

The index will have entries like:

CHRIS
BERT
JOE

and so on.

If you run a query like:

select * from table where UPPER(name) = 'CHRIS';

It's an easy match.

If you don't create an UPPER index, it has to do a comparison with each
row - so the index can't be used because postgres has to convert the
field to upper and then do the comparison.

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