اخواني اريد ان اعرف ماهو هذا ال parameter
cursor sharing
وبياخد 3 قيم
exact, force and similar
فما هو الفرق بينهم
تحياتي لكم

EXACT - (Default) Only statements with an exact text match will share the same SQL area.
SIMILAR - Oracle will substitute bind variable for all literals, thereby increasing the chances of a text match. Oracle will force similar statements to share the SQL area without deteriorating execution plans.
FORCE - The same as SIMILAR except that execution plans may deteriorate. This option should only be used if the risk of suboptimal plans is outweighed by the increase in cursor sharing.
In an ideal world the application should be written to encourage cursor sharing, but existing applications may gain reduced memory usage, faster parses, and reduced latch contention when using this option.

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if a SQL statment is executes it will be stored in the shared SQL Area in the Shared Pool.

Cursor Sharing:
EXACT-when the same SQL statement is executed again it will be retrieved from the Shared SQL Area in memory not from disk which will be fast.

SIMILAR :if one SQL statment like this
select ename from emp
where empid=10;
is executed it will be saved in the shared SQL Area.and when another SQL statemnt is executed like this
select ename from emp
where empid=20;
it will be retrieved from the Shared SQL Area like the old one but substitute the empid in the 2 SQLs

FORCE : The same as SIMILAR except that execution plans of SQL Statements may be different.



sorry for using English,but the DBA work has to be in English