Re: Why fetch a row is more slow than a 'selec * from'

Hello

cursors are optimized for fast return of first row and there are no
expect to return complete result.

This can be a problem

try to set cursor_tuple_fraction to 1

Regards

Pavel Stehule

2011/11/7 Ing.Edmundo.Robles.Lopez <erobles(at)sensacd(dot)com(dot)mx>:
> Hello
> I've been looking for ways to optimize a query.
>
> I have a table with 120,000 records. When searched on:
>
> select * from big_table
>
> takes to run: 3 min.
>
> I wanted to use cursors and the query with big_table,  it taked 11 minutes.
> It caught my attention  on a  small_table (100 records) because  the time,
> with cursors, were reduced by half.
>
>
> The EXPLAIN ANALYZE: indicates that a search is sequential, but has a
> primary key
>
>
>
> Will have some advice to optimize the response time of the visit? there is
> nothing to do? :(
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