Is this a planner bug?

Hi,

I got this plan:

Limit  (cost=0.00..1.12 rows=1 width=0)
   ->  Seq Scan on fmb  (cost=0.00..6964734.35 rows=6237993 width=0)
         Filter: ...

The table has ~80,000,000 rows. So, the filter, according to the plan,
filters out >90% of the rows. Although the cost for the first row to
come out of the seqscan might be 0, the cost for the first row to pass
the filter and, hence, to hit the limit node is probably higher.

Thanks,
Torsten