Monthly Archives: June 2016

Gather Stats on Function based filter condition in oracle

For one of performance improvement, identify root cause for bad execution plan was incorrect cardinality estimation on function based condition on a table column. As part of recommendation, we just needed to get estimated cardinality improve on table filter conditions. … Continue reading

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Alias on Rownum might degrade performance in oracle.

We use First’s row filtering(using Rownum) for lot of day to day functional implementation, Pagination being one of the best example. Rownum clause is best way to impose First – N Rows optimization and restrict subset of projected rows as … Continue reading

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