Abandoned wrote:
> Hi..
> I want to do index in database.
> My table:
> id(int) | id2(int) | w(int) | d(int)
>
> My query:
> select id, w where id=x and id2=y (sometimes and d=z)
>
> I have too many insert and select operation on this table.
> And which index type can i use ? Btree, Rtree, Gist or Hash ?
> Also I want to unique (id, id2)..
> Now this is my index. is it give me good performance ?
> CREATE UNIQUE INDEX ind1 ON test USING btree (id, id2)
> CREATE INDEX ind2 ON test USING btree (id)
> CREATE INDEX ind3 ON test USING btree (id2)
> CREATE INDEX ind4 ON test USING btree (w)
> CREATE INDEX ind5 ON test USING btree (d)
>
> I'm too sorry my bad english.
> King regards..

If you only ever use d=z in conjunction with id=x and id2=y, then I would go
for a single index of
(id, id2, d).
Depending on the structure of your data, you might simply make this the only
index (primary key).