Cannot interpret EXPLAIN - Mailing list pgsql-performance

From Jörg Kiegeland
Subject Cannot interpret EXPLAIN
Date
Msg-id 499ACAC4.8010608@ikv.de
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

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