Entity Framework 6 模型优先迁移

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期望的结果:

在实体框架中使用模型优先方法，并允许根据模型中的更改自动更改已部署的数据库/模型.自动生成架构差异脚本以实现平滑迁移.

Use model first approach with Entity Framework and allow changes to deployed database/ model to be done automatically based on the changes in the model. Automatic schema difference script generation to allow smooth migrations.

有没有办法在模型优先 EF6 中执行迁移?我可以看到到处都是代码优先迁移主题，但在 Model First 上什么都没有.

Is there a way to perform migrations in model first EF6? I can see code first migrations topics all over, but nothing much on Model First.

目前我看到的选项:

• 数据库生成电源组(似乎已过时)
• 先以某种方式转换为代码，然后使用迁移(不可取，因为我喜欢有视觉设计师)
• 以某种方式搭载代码优先迁移(blog.amusedia/2012/08/entity-framework-migration-with-model.html:这是针对 EF5，出现无法在 Model First 上运行迁移的错误)
• 一些第三方工具?

• Database generation power pack (seems outdated)
• somehow convert to code first, then use migrations (not desirable, as I like to have a visual designer)
• somehow piggy back on code first migrations (blog.amusedia/2012/08/entity-framework-migration-with-model.html : this is for EF5, got error that can't run migrations on Model First)
• some third party tools?

推荐答案

据我所知目前还没有自动迁移Entity framework model first.

As far as I know there still is no automatic migration for Entity framework model first.

我们的做法是:

从模型创建一个新的数据库.

创建差异脚本以将旧数据库迁移到新数据库.

验证此差异脚本确实正确.始终仔细检查您的自动化工具创建的内容.

我们首先使用 Open DB diff 进行模型首次迁移.之后我们切换到 Redgate 的 SQL 比较，因为它产生了更可靠的迁移.根据我们的经验，DbDiff 产生了很多不必要的 SQL，因为它影响了列的顺序，并且还有一些其他问题，例如不断删除和重新添加外键.除此之外，它仍然可以正常工作，但我们必须对其生成的 SQL 进行大量的双重检查.

We first used Open DB diff for our model first migrations. After that we switched to Redgate's SQL compare because it produced more reliable migrations . In our experience DbDiff produced a lot of unnecessary SQL because it bothers with the order that columns are in, and has some other issues like foreign keys constantly being dropped and re-added. Aside from that it still did the job fine, but we had to do a lot of double checking on its generated SQL.