检查Rails中是否存在表 - Check if a table exists in Rails

问题：

I have a rake task that won't work unless a table exists. 我有一个rake任务，除非存在一个表，否则它将无效。 I'm working with more than 20 engineers on a website so I want to make sure they have migrated the table before they can do a rake task which will populate that respective table. 我正在一个网站上与20多名工程师一起工作，所以我想确保他们已经迁移了表，然后才能执行一个rake任务，该任务将填充相应的表。

Does AR have a method such as Table.exists ? AR有一个像Table.exists这样的方法吗？ How can I make sure they have migrated the table successfully? 如何确保他们已成功迁移表？

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解决方案：

参考一： https://en.stackoom.com/question/ReO3
参考二： https://stackoom.com/question/ReO3