OCP 1Z0 052 138

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138. Your database is configured in shared server mode. However, your senior DBA asks you to modify
the value of the PRIVATE_SGA limit in the profile of the users. What could be the reason for this?
A.to limit the User Global Area (UGA) memory allocated to a session from the SGA
B.to limit the amount of memory to be used for the dispatcher queue of a session in SGA
C.to limit the amount of memory to be used for the request pool in System Global Area (SGA)
D.to control the amount of memory allocated in SGA for the local variables for each shared server process
Answer: A

http://docs.oracle.com/cd/E11882_01/server.112/e41084/statements_2009.htm#SQLRF00814

ALTER RESOURCE COST

PRIVATE_SGA

Use this clause to apply a weight to the PRIVATE_SGA resource. This limit applies only if you are using shared server architecture and allocating private space in the SGA for your session.

http://docs.oracle.com/cd/E11882_01/server.112/e40540/memory.htm#CNCPT1239

Private SQL Area

A private SQL area holds information about a parsed SQL statement and other session-specific information for processing. When a server process executes SQL or PL/SQL code, the process uses the private SQL area to store bind variable values, query execution state information, and query execution work areas.

Do not confuse a private SQL area, which is in the UGA, with the shared SQL area, which stores execution plans in the SGA. Multiple private SQL areas in the same or different sessions can point to a single execution plan in the SGA. For example, 20 executions of SELECT * FROM employees in one session and 10 executions of the same query in a different session can share the same plan. The private SQL areas for each execution are not shared and may contain different values and data.

A cursor is a name or handle to a specific private SQL area. As shown in Figure 14-5, you can think of a cursor as a pointer on the client side and as a state on the server side. Because cursors are closely associated with private SQL areas, the terms are sometimes used interchangeably.

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