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Oct 31, 2007 at 06:37 AM

Cardinality or full table scans

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Hello,

I'm seeing the execution plans in 10g that have total Estimate #Rows = 0 for full table scans. This doesn't make sense.

eg.

SELECT

 "MATNR" , "WERKS" , "BWTAR" , "CHARG"

FROM

"MCHA"

WHERE

"MANDT" = :A0#

Execution Plan

Explain from gv$sql_plan: Address: C00000057CCCC028 Hash_value: 22

Parse Timestamp: 20071030 14:18:34

SELECT STATEMENT ( Estimated Costs = 3.137 , <b>Estimated #Rows = 0</b> )

1 TABLE ACCESS FULL MCHA

( Estim. Costs = 3.136 , Estim. #Rows = 1.134.670 )

Estim. CPU-Costs = 928.730.441 Estim. IO-Costs = 2.936

Filter Predicates

How can Estim. #Rows = 1.134.670 for the outer FULL SCAN while at the same time Estimated #Rows = 0 for the SELECT?

Kind regards,

Peter