Cannot interpret EXPLAIN

From: Jörg Kiegeland
Subject: Cannot interpret EXPLAIN
Date: ,
Msg-id: 499ACAC4.8010608@ikv.de
(view: Whole thread, Raw)
List: pgsql-performance

Hi,

I have a query  SELECT * FROM myTable WHERE ((myCol = var1) OR (myCol =
var2))

.. which produces the following EXLAIN output:


Index Scan using myIndex on myTable (cost=0.00..8.28 rows=1 width=537)
  Filter: ((myCol = $1) OR (myCol = $2))


The index "myIndex" is an index on column "myCol". However I expected an
"Index Cond:" row instead of a "Filter:" row, which normally indicates
performance problems.
Should I rather split the OR and use two SELECT statements to get my
result (var1!=var2)? Namely in this case, "Index Cond:" is outputed by
EXPLAIN.

--Jörg Kiegeland


pgsql-performance by date:

From: Rusty Conover
Date:
Subject: Re: TCP network cost
From: "Ross J. Reedstrom"
Date:
Subject: Re: TCP network cost