Re: [SQL] indexes

Remigiusz Sokolowski wrote:
> 
> Hi!
> I try to optimize following query
> SELECT DISTINCT e1.name_ent AS nazwa_grupy
> FROM ent e1, binds b1, ent e2
> WHERE e1.id_ent=b1.id_parent AND b1.id_child=e2.id_ent AND b1.id_links=0
             ^^^^^^^^^^^^^
 
> AND e2.name_ent='SERWIS';
> 
> Is it possible to get better results? From explain notes it looks, that
> engine uses indexes on ent table, but I can't constrain it to use any
> index on binds table - this causes main problem.
> Or may be query should look in other way?
> 
...
> Table    = binds2_idx
> +--------------------+----------------------------------+------+
> |Field               |              Type                |Length|
> +--------------------+----------------------------------+------+
> | id_parent          | int4                             |4     |
> | id_child           | int4                             |4     |
> | id_links           | int4                             |4     |
> +--------------------+----------------------------------+------+

Try to create index on binds (id_links, id_parent, id_child)

Vadim