Oracle sql statement processing steps.

Whenever a SQL statement is submitted to execute, Oracle goes through the below mentioned steps

1. Check for identical statements in memory to avoid performance overhead due to parsing.
2. Allocate memory in shared memory area.
3. Evaluate the syntax of the statement to check whether all the oracle key words are spell correctly.
4. Do semantic check, where all the objects (tables or columns) are validated and check for the user's privilege to access these objects.
5. Form an execution plan to execute the statement.

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Hope this is useful. Thanks Phoenix