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Cursor Sharing itself was designed to work around performance problems caused by applications that do not use bind variables. The database notices similar statements when parsing. The SQL area used to process the first occurrence of a statement is used to process subsequent occurrences. Only one shared SQL area exists for a unique statement. Because shared SQL areas are in Shared Memory, any process can use a shared SQL area. Sharing of SQL areas reduces memory use on the database server, thereby increasing performance. 

With Adaptive Cursor Sharing, the database compares the effectiveness of execution plans between executions with different bind variable values. If it notices suboptimal plans, it allows certain bind variable values, or ranges of values, to use alternate execution plans for the same statement.

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