Hello Stephen,
I was created with SQL :
CREATE INDEX IF NOT EXISTS "t_idx_1" ON MYSCHEMA."t" ("a", "b", "c");
BR,
Chrystophe Vergnaud
Architect @ Cyblex Technologies
Le jeu. 16 déc. 2021 à 13:51, Stephen Darlington <
stephen.darling...@gridgain.com> a écrit :
> Can you show how you’ve defined your index(es)?
>
> > On 16 Dec 2021, at 12:27, Chrystophe Vergnaud <
> chrystophe.vergn...@gmail.com> wrote:
> >
> > Hello,
> >
> > I'm running an ignite 2.10 and I don't understand the behavior of the
> multi-columns index.
> >
> > For instance, I have a table t(id, a,b,c, d, e, f, g)
> > - id is a uuid and is the key
> > - a is a TIMESTAMP
> > - b is a SMALLINT
> > - c is a TINYINT
> > - e, f, g are VARCHAR
> >
> > this table have around 200M lines
> >
> > I have to select data based on a, b, c in this order, so basically, I
> have setup an index on (a,b,c)
> >
> > If I apply a select with a WHERE clause on "a>=x AND a < y", it works
> perfectly, the response time is ok (using USE INDEX)
> >
> > If I add the b in the WHERE clause I expect to optimize the response
> time but it is not the case. Worst, if the value of b is not present in the
> slice, it is responding as if the b was not in the WHERE clause at all (it
> seems to run a full scan on the sub-result)
> >
> > Do I miss something ? is it related to the implementation of the B+tree ?
> >
> > Thanks in advance for your help.
> >
> > Best regards,
> >
> > Chrystophe Vergnaud
> > Architect @ Cyblex Technologies
>
>
>
