注意：当索引表达式被用于关系表达式，或作为某个操作符类函数的参数时，查询优化器将考虑使用函数索引。

Note: the query optimizer considers using a functional index when the index expression is used in a relational expression or as an argument to one of the operator class functions.

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展示如何创建xml索引以及如何使用DAD中的信息创建索引的XML表达式。

Show how to create XML indexes and how to use information in the DAD to create the XML expression for the index.

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算术表达式包含START _ date列使得谓词不可索引。

The arithmetic expression involving the START_DATE column makes the predicate non-indexable.

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