If an application is not performing adequately, it is generally more desirable to add more columns to an existing index, or add new indexes to a table as your first options.

如果一个应用程序执行时的性能不合格，较为可取的做法通常是添加更多的列到现有的索引中，或者为一个表添加新的索引，这种做法是首选。

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If an application is not performing adequately, it is generally more desirable to add more columns to an existing index, or add new indexes to a table as your first options.

如果一个应用程序执行时的性能不合格，较为可取的做法通常是添加更多的列到现有的索引中，或者为一个表添加新的索引，这种做法是首选。

youdao