Interview Questions
Oracle DBA
Performance Tuning
Oracle DBA
Performance Tuning
The EXPLAIN PLAN statement displays execution plans chosen by the Oracle optimizer for SELECT, UPDATE, INSERT, and DELETE statements. A statement's execution plan is the sequence of operations Oracle performs to run the statement.
It shows the following information in a statement:
- Ordering of the tables
- Access method
- Join method for tables
- Data operations ( filter, sort, or aggregation)
- Optimization ( cost and cardinality of each operation)
- Partitioning (set of accessed partitions)
- Parallel execution (distribution method of join inputs)
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