Heh, what's this?

Karl Denninger <karl@mcs.net>

From: Karl Denninger <karl@mcs.net>
To: hackers@postgresql.org
Date: 1998-03-09T19:23:54Z
Lists: pgsql-hackers
The following query returns:

explain update user set inter = person.inter where person.custid = user.custid;

NOTICE:  QUERY PLAN:
 
 Nested Loop  (cost=1095.16 size=1 width=370)
   ->  Seq Scan on person  (cost=1095.16 size=16035 width=8)
   ->  Seq Scan on user  (cost=0.00 size=0 width=362)
      
EXPLAIN

Uh, this is a problem.

Both person and user have an index on "custid".  6.2.1 used to utilize them.

You have to do a sequential scan on user, but NOT on person to perform 
this update.

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