The SQL compiler USES them to transform a statement into a more optimized form, thus improving the access path to the required data.

SQL编译器使用信息约束将语句转化成更优的形式，从而改善对所需数据的访问路径。

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The SQL compiler USES them to transform a statement into a more optimized form, thus improving the access path to the required data.

SQL编译器使用信息约束将语句转化成更优的形式，从而改善对所需数据的访问路径。

youdao