Versioning helps comparing different versions of the schema and the developer can roll back and forth the changes performed.

版本控制有助于比较schema的不同版本，开发者可以对已进行的变更进行回退和重做处理。

youdao

First, there was what Dad called the 'log roll' in which he would roll back and forth on the living room carpet while we kids had to jump over him without getting nabbed.

首先，是爸爸叫做“滚原木”的游戏，他在客厅的地毯上滚来滚去，我们会跳过他而不被捉到。

youdao

And sometimes I spread that Baptist pallet out on the floor, and Lily and I roll a ball back and forth.

有的时候，我把洗礼约翰盘摆在地上，丽丽和我来来回回的滚动。

youdao

The app displays each moment as a long film roll that users can scroll back and forth on, or watch as a time-lapse video.

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He added that he hoped the two sides "don't get involved in some kind of typical Washington back-and-forth sideshow here and rather just ... roll up their sleeves and get to work" on writing a comprehensive immigration bill.

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