You might specify to both add and drop database partitions on the same command but the add must come before the drop.

可以在同一个命令上同时指定添加和删除数据库分区，但是必需先添加，后删除。

youdao

You can add and drop indexes; alter tables by dropping, renaming, or adding columns; and even drop down into SQL as necessary.

可以添加和删除索引；通过删除、改名或添加列来修改表；甚至在必要的时候借助于SQL。

youdao

A script might drop all tables and add all of the tables again.

脚本可能会删除所有的表，再添加所有的表。

youdao

At the top of the screen you will see the tools tab and from the drop down menu select add-ons.

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In addition, customers can add documents using an SD card, Adobe Digital Editions, or drag-and-drop.

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Publishers can drag and drop to add in XML feeds, videos and other third-party web applications (such as weather and movie listings) and add them into mobile ads.

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