ExecInitIndexScan ERROR?

Hi,

I just got the following error message and have no clue what I'm doing wrong:

ERROR:  ExecInitIndexScan: both left and right op's are rel-vars


Everything works fine with the following query:

explain select p0.protein
from dom_prot p0, dom_prot p1, dom_prot p2, dom_prot p3
where p0.protein = p1.protein
and p1.protein = p2.protein
and p0.start < p1.start
and p1.start < p2.start
and p0.domain = 'SH3'
and p1.domain = 'SH2'
and p2.domain = 'SH3';

NOTICE:  QUERY PLAN:

Nested Loop  (cost=6.05 size=1 width=48)
  ->  Nested Loop  (cost=4.05 size=1 width=32)
        ->  Index Scan on p2  (cost=2.05 size=1 width=16)
        ->  Index Scan on p1  (cost=2.00 size=1 width=16)
  ->  Index Scan on p0  (cost=2.00 size=1 width=16)


EXPLAIN


Adding one to the 'from' list leads to the error message. Here' the query and
it's plan:

explain select p0.protein
from dom_prot p0,
dom_prot p1,
dom_prot p2,
dom_prot p3   -- the new guy
where p0.protein = p1.protein
and p1.protein = p2.protein
and p0.start < p1.start
and p1.start < p2.start
and p0.domain = 'SH3'
and p1.domain = 'SH2'
and p2.domain = 'SH3';

NOTICE:  QUERY PLAN:

Nested Loop  (cost=3088.11 size=64517 width=52)
  ->  Nested Loop  (cost=6.05 size=1 width=48)
        ->  Nested Loop  (cost=4.05 size=1 width=32)
              ->  Index Scan on p2  (cost=2.05 size=1 width=16)
              ->  Index Scan on p1  (cost=2.00 size=1 width=16)
        ->  Index Scan on p0  (cost=2.00 size=1 width=16)
  ->  Seq Scan on p3  (cost=3082.06 size=64517 width=4)

EXPLAIN


As it might have something to do with my indices (??), here's what they look
like:

  CREATE INDEX dp_domain_ind
     ON dom_prot USING btree(domain text_ops);
  CREATE INDEX dp_score_ind
     ON dom_prot USING btree(score int4_ops);

And the table itself is:

  CREATE TABLE dom_prot
     (
        domain text not null,
        protein text not null,
        start int4 not null,
        ende int4 not null,
        score int4,
    e_value float8,
    p_value char16,
        primary key (domain, protein, start, ende)
     );

Sorry for that quite extensive mail,

Joerg

--
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