Re: [INTERFACES] Re: [HACKERS] changes in 6.4

Bruce Momjian wrote:
>
> > The results are profound.    Queries that used to scan tables because of the
>
> How about if instead of doing:
>
>         select * from tab1 where val = 3
>         union
>         select * from tab1 where val = 4
>         ...
>
> you change it to:
>
>         select * from tab1 where val in (
>                 select 3
>                 union
>                 select 4
>         )
>

the explosion happens for ORs of multiple ANDs that get rewritten to:

select * from tabl wehere val1=1 and val2=1 and val3=1
union
select * from tabl wehere val1=1 and val2=1 and val3=2
union
...


And there is no way of doing (at least presently):

select * from table where (val1,val2,val3) in (select 1,1,1 union select
1,1,2);

Hannu