RE: Tuning By cardinality Estimates

A common example of correlated join criteria would be:

select . . .
where make='FORD'
and model='MUSTANG';

The CBO doesn't know that all Mustangs are built by Ford, so it's not aware 
that the extra filter condition won't really filter out any more rows.

Regards,
Brandon

-----Original Message-----
From: oracle-l-bounce@xxxxxxxxxxxxx [mailto:oracle-l-bounce@xxxxxxxxxxxxx] On 
Behalf Of hrishy

I didnt quite understand the statement
"Check if the join criteria between SC and SH are correlated"


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