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Prepared Property
Indicates whether to save a compiled version of a command before execution.

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Remarks
Use the Prepared property to have the provider save a prepared (or compiled) version of the query specified in the CommandText property before a Command object's first execution. This may slow a command's first execution, but once the provider compiles a command, the provider will use the compiled version of the command for any subsequent executions, which will result in improved performance.

If the property is False, the provider will execute the Command object directly without creating a compiled version.

If the provider does not support command preparation, it may return an error as soon as this property is set to True. If it does not return an error, it simply ignores the request to prepare the command and sets the Prepared property to False.