Re: optimizer and bind variables

It's mentioned in a couple of places as 'peeking' at bind variables.

The first time the optimizer sees a SQL statement with bind variables, it checks the actual input values and uses those values to generate an execution path. Thereafter, the same path is used for that SQL text, regardless of the actual values for the bind variables in the subsequent uses of the text.

This behaviour also appears if you use cursor_sharing=force, but can be modified if you use cursor_sharing=exact.

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Practical Oracle 8i: Building Efficient Databases


Steffen Ramlow wrote in message ...


>> When you have literals you are giving the optimizer more information to

>> work with.  In 9i, the optimizer can "take a glance" at the value of

>> bind variables under certain circumstances

>

>are u sure? where is this documented?

>and btw: i'm using 8.1.7

>

>