Thread: searching using indexes 8.3

LARC/J.L.Shipman/jshipman wrote:
>  EXPLAIN ANALYZE SELECT * FROM itemsbyauthor;
>                                                     QUERY PLAN
> -------------------------------------------------------------------------------------------------------------------
>
>  Seq Scan on itemsbyauthor  (cost=0.00..971.34 rows=53634 width=34)
> (actual time=0.029..25.831 rows=53634 loops=1)
>  Total runtime: 34.851 ms
> (2 rows)
>
>
> I have an index for the table, but it is not being utilized.  Why is
> this?  How do I get the index to be used?

An index to fetch all the rows from a table? How would that help?

--
   Richard Huxton
   Archonet Ltd

On Monday 10 March 2008, LARC/J.L.Shipman/jshipman
<jeffery.l.shipman@nasa.gov> wrote:
> Hi,
>     When I do a search such as:
>
>   EXPLAIN ANALYZE SELECT * FROM itemsbyauthor;
>                                                      QUERY PLAN
> ------------------------------------------------------------------------
> -------------------------------------------
>   Seq Scan on itemsbyauthor  (cost=0.00..971.34 rows=53634 width=34)
> (actual time=0.029..25.831 rows=53634 loops=1)
>   Total runtime: 34.851 ms
> (2 rows)
>
>
> I have an index for the table, but it is not being utilized.  Why is
> this?  How do I get the index to be used?
>

You asked for the whole table. How would an index help?


--
Alan

On Mar 10, 2008, at 6:33 PM, LARC/J.L.Shipman/jshipman wrote:

> Hi,
>     When I do a search such as:
>
>  EXPLAIN ANALYZE SELECT * FROM itemsbyauthor;
>                                                     QUERY PLAN
> ----------------------------------------------------------------------
> ---------------------------------------------
>  Seq Scan on itemsbyauthor  (cost=0.00..971.34 rows=53634 width=34)
> (actual time=0.029..25.831 rows=53634 loops=1)
>  Total runtime: 34.851 ms
> (2 rows)
>
>
> I have an index for the table, but it is not being utilized.  Why
> is this?  How do I get the index to be used?


To fetch all rows unordered from a table the fastest method is a
sequential scan. An index scan would be slower, probably significantly.

Alban Hertroys

--
If you can't see the forest for the trees,
cut the trees and you'll see there is no forest.


!DSPAM:737,47d5748b233097069826464!