"Clinton James" <cjames(at)callone(dot)net> writes:
> # explain select * from ld where cust_num = '10102899';
> NOTICE: QUERY PLAN:
> Seq Scan on ld (cost=0.00..20810.83 rows=8989 width=128)
The reason it's not using an indexscan is that it thinks it's going to
find 8989 matches (and if that were true, a seqscan probably *is* the
right plan). You must have some extremely-often-repeated entries in
that column; what are they, and can you get rid of them?
regards, tom lane