从EF6.1开始，您可以使用拦截器来注册数据库记录器。 请参见“拦截器”和“记录数据库操作”章节

<configuration>
  <entityFramework>
    <interceptors> 
      <interceptor type="System.Data.Entity.Infrastructure.Interception.DatabaseLogger, EntityFramework"> 
        <parameters> 
          <parameter value="C:\Temp\LogOutput.txt"/> 
          <parameter value="true" type="System.Boolean"/> 
        </parameters> 
      </interceptor> 
    </interceptors>
  </entityFramework>
</configuration>

有两种方法:

To view the SQL that will be generated, simply call ToTraceString(). You can add it into your watch window and set a breakpoint to see what the query would be at any given point for any LINQ query. You can attach a tracer to your SQL server of choice, which will show you the final query in all its gory detail. In the case of MySQL, the easiest way to trace the queries is simply to tail the query log with tail -f. You can learn more about MySQL's logging facilities in the official documentation. For SQL Server, the easiest way is to use the included SQL Server profiler.

我正在做集成测试，需要在实体框架核心2.1中调试生成的SQL语句，所以我使用DebugLoggerProvider或ConsoleLoggerProvider，如下所示:

[Fact]
public async Task MyAwesomeTest
    {
        //setup log to debug sql queries
        var loggerFactory = new LoggerFactory();
        loggerFactory.AddProvider(new DebugLoggerProvider());
        loggerFactory.AddProvider(new ConsoleLoggerProvider(new ConsoleLoggerSettings()));

        var builder = new DbContextOptionsBuilder<DbContext>();
        builder
            .UseSqlServer("my connection string") //"Server=.;Initial Catalog=TestDb;Integrated Security=True"
            .UseLoggerFactory(loggerFactory);

        var dbContext = new DbContext(builder.Options);

        ........

下面是Visual Studio控制台的输出示例:

EF Core 5.0+

这个期待已久的功能在EF Core 5.0中可用!这是每周的状态更新:

var query = context.Set<Customer>().Where(c => c.City == city); Console.WriteLine(query.ToQueryString()) results in this output when using the SQL Server database provider: DECLARE p0 nvarchar(4000) = N'London'; SELECT [c].[CustomerID], [c].[Address], [c].[City], [c].[CompanyName], [c].[ContactName], [c].[ContactTitle], [c].[Country], [c].[Fax], [c].[Phone], [c].[PostalCode], [c].[Region] FROM [Customers] AS [c] WHERE [c].[City] = @__city_0 Notice that declarations for parameters of the correct type are also included in the output. This allows copy/pasting to SQL Server Management Studio, or similar tools, such that the query can be executed for debugging/analysis.

哦吼! !

(注意:你需要使用Microsoft.EntityFrameworkCore;)

SQL Management Studio => Tools => SQL Server分析器

File =>新建跟踪…

使用Template =>空白

事件选择=> T-SQL

左侧检查:SP.StmtComplete

列筛选器可用于选择特定的ApplicationName或DatabaseName

启动该概要文件运行，然后触发查询。

点击这里获取来源信息

对于那些使用Entity Framework 6及以上版本的用户，如果你想在Visual Studio中查看输出SQL(就像我做的那样)，你必须使用新的日志/拦截功能。

添加下面这行代码将在Visual Studio输出面板中输出生成的SQL(以及其他与执行相关的详细信息):

using (MyDatabaseEntities context = new MyDatabaseEntities())
{
    context.Database.Log = s => System.Diagnostics.Debug.WriteLine(s);
    // query the database using EF here.
}

有关登录EF6的更多信息，请参阅这个漂亮的博客系列:http://blog.oneunicorn.com/2013/05/08/ef6-sql-logging-part-1-simple-logging/

注意:确保在DEBUG模式下运行项目。