Re: Rewritten queries

--- Keith Worthington <keithw(at)narrowpathinc(dot)com>
escribió:
> Hi All,
>
> I wrote a query that created a view and when I
> looked at it in the database
> the SELECT statement was very different.
> ...
> Is this expected behavior?

Yes. Sometimes postgres will rewrite your queries.

> Should I be concerned?

Actually, no. If a query has to be rewritten Postgres
always will rewrite the query before execution. In a
view it doesn't want to do that every time so it
create the view with the modified query.

> Is the modified query faster?

Sometimes, but not necesarilly.

> Better in some way?

I think is just a way to manage different sintaxis
that do the same. But i can be wrong.

For example queries with field1 IN (value1, value2)
will be rewritten like
(field1 = value1 or field1 = value2)

> Should I be writing my queries to conform with
> the modified syntax?
>
If u want. I do not if u can gain some performance
when the query will be no rewritten. I do not.

regards,
Jaime Casanova

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