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…Shared Pool Reuse
Statement must match:
- case
- comments
- white space (blanks, tabs)
- objects referenced
- bind variables must match
Statements must be semantically equivalent
Using PL/SQL procedures typically increases shared pool reuse
Notes:
SQL statements need to be identical to be considered equivalent. Because of the different case used in the table name, the following statements are NOT identical:
SELECT ename, sal FROM emp WHERE deptno = 20;
SELECT ename, sal FROM EMP WHERE deptno = 20;
Not only do statements need to be match syntactically and character-by-character, they must be semantically the same. For example, the clause “FROM emp” could mean DAVE.EMP or PRODUCTION.EMP, depending on who is executing the query.
Using stored PL/SQL and bind variables will increase the likelihood of matching SQL because many sessions tend to execute the same procedures.