1. Include VPD predicates: If Virtual Private Database (VPD, formerly known as row-level security)
is in use and active for one of the tables referenced in the parsed SQL
statement, the predicates generated by the security policies are included in
its WHERE clause.
2. Check syntax, semantics, and access
rights: This step makes sure not only that the SQL statement is correctly
written but also that all objects referenced by the SQL statement exist and the
user parsing it has the necessary privileges to access them.
3. Store parent cursor in a shared SQL
area: Whenever a shareable parent cursor isn’t yet available, some
memory is allocated from the library cache, and a new parent cursor is stored
inside it.
4. Generate execution plan: During this phase, the query optimizer produces an execution plan
for the parsed SQL statement.
5. Store child cursor in a shared SQL area: Some memory is allocated, and the shareable child cursor is
stored inside it and associated with its parent cursor.
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