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Re: How ad an increasing index to a query result?

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On 18/10/2009 11:30, Alban Hertroys wrote:

> Short of enumerating those results in your application, the easiest
> approach is probably to wrap your query in a join with generate_series
> like so:
> 
> SELECT a, s.b
> FROM (
>     SELECT a
>     FROM table1
>     ORDER BY a DESC LIMIT 5
> ) AS t1, generate_series(5, 1, -1) AS s(b)
> 

Won't that just give you the cartesian product of the two sets? I tried
something similar yesterday out of curiosity, and that's what I got.

The only things I can think of are (i) as you say, enumerate the results
in the application or (ii) use a temporary sequence as someone else
suggested.

Ray.

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