I do not under stand the following explain output (pgsql 8.0.3):

explain analyze
select b.e from b, d
where b.r=516081780 and b.c=513652057 and b.e=d.e;

                                                        QUERY PLAN
Nested Loop (cost=0.00..1220.09 rows=1 width=4) (actual time=0.213..2926.845 rows=324503 loops=1) -> Index Scan using b_index on b (cost=0.00..1199.12 rows=1 width=4) (actual time=0.104..17.418 rows=3293 loops=1)
        Index Cond: (r = 516081780::oid)
        Filter: (c = 513652057::oid)
-> Index Scan using d_e_index on d (cost=0.00..19.22 rows=140 width=4) (actual time=0.009..0.380 rows=99 loops=3293)
        Index Cond: ("outer".e = d.e)
Total runtime: 3638.783 ms
(7 rows)

Why is the rows estimate for b_index and the nested loop 1? It is actually 3293 and 324503.

I did VACUUM ANALYZE before and I also increased the STATISTICS TARGET on b.e to 500. No change.

Here is the size of the tables:

select count(oid) from b;

select count(oid) from b where r=516081780 and c=513652057;

select count(oid) from d;



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