Subject | Question about index use |
---|---|
Author | Carsten_Sch=c3=a4fer |
Post date | 2019-03-05T14:14:14Z |
Hi,
I'm using FB 3.0.4 on Windows and i'm asking why the index (on field_B)is not used in the follwing query?
Select * from table_A a left join table_B b on a.field_A = b.field_A where b.field_B = 1;
field_A is a standard foreign key and field_B is an indexed field but the index is not used and so the query is slow (for big tabels).
When i use an inner join the index on field_B is used, but i don't get why FB has to make a difference in this case.
The result set should always be the same,
regardless of inner join or left join, or not?
Regards
Carsten