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Different Execution Plans for 2 instances of the same database.. Why??.. Help me out

 
Sajee Joseph
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Hello all,
I have a problem with Execution Plan
Here I have a SQL query, which I am running on 2 databases. The 2 databases are same snapshots but at different locations. The local database
( database which is on local server ) is giving different SQL Execution planand the remote database is giving different execution plan.
All the init.ora parameters are same. Both the databases have same tables and same number of records every thing is same. Even then, why it is giving different Execution plans.
The only major difference it showing is, at local database, at one point/level the execution plan is using the "HASH JOIN", whereas in remote database at the same point/level, the execution plan it is using "NESTED LOOPS". Why it so ?
Please Help me out.
Regards,
Saj
 
SJ Adnams
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table has not been analysed i guess?
 
Loren Rosen
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different indexes
instances were analyzed at different times (or one not at all)
different Oracle versions
 
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