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对不存在的数据库进行单元测试的最佳方法

[英]Best way to Unit test non-existing Database

原文 2016-09-26 06:55:12 6 2 c#/ sql/ database/ unit-testing

We have a build server which does not have a database running on its machine. 我们有一个构建服务器，它的计算机上没有运行数据库。 Now we want to make unit tests which also cover SQL-related tasks, for example writing mock-data and reading them again to verify the output (it gets manipulated by C# code in the process). 现在，我们要进行单元测试，其中还涉及与SQL有关的任务，例如编写模拟数据并再次读取它们以验证输出（该过程在过程中由C＃代码操纵）。

So the common approach would be to provide a connection-string to the remote server which actually runs a database. 因此，通常的方法是为实际运行数据库的远程服务器提供连接字符串。 This works, but it is unwanted because the database-server could be inaccessible when the build is triggered, and therefore the automatic tests would fail . 这可以工作，但是这是不希望的，因为触发构建时可能无法访问数据库服务器，因此自动测试将失败。

What is the best way to create a "pseudo-database" while running Unit tests? 在运行单元测试时创建“伪数据库”的最佳方法是什么？ Is this even possible without an actual database? 如果没有实际的数据库，这甚至可能吗？ Does it even make sense? 有道理吗？

2 个解决方案

Use mocking framework like Moq , check here . 使用Moq类的Moq框架，请在此处检查。 That is the exact purpose of the Mocking frameworks that only a given component can be unit tested and any integration like database can be mocked to return the valid pre-defined result at the run-time and thus determine the working of given code / unit 这就是Mocking框架的确切目的，即只能对给定的组件进行单元测试，并且可以模拟任何集成（如数据库）以在运行时返回有效的预定义结果，从而确定给定代码/单元的工作方式

The commonly accepted answer to "how do I unit test something with external dependencies" is to use a mocking layer. 关于“如何使用外部依赖项对单元进行单元测试”的公认答案是使用模拟层。

However, that very quickly becomes unwieldy - you end up writing and maintaining a lot of code just to mimic your database, and it's not clear this code will pay for itself. 但是，这很快变得很笨拙-您最终只是为了模仿数据库而编写并维护了大量代码，并且尚不清楚该代码是否能为自己带来回报。 For instance, if your SQL statements has a typo, your unit tests won't catch that. 例如，如果您的SQL语句有错别字，则单元测试将无法捕获错字。

Instead, it is much better to factor the code which manipulates the data out into a layer which can be unit-tested without database access. 取而代之的是，将处理数据的代码分解为一层，而无需数据库访问即可进行单元测试，这要好得多。