显示调用 SaveChanges() 时 Entity Framework Core 为 PostgreSQL 生成的数据库查询

Question

我已经为 postgreSQL 创建了实体框架核心的数据库第一个实现。 我尝试了一个简单的项目创建和保存，但出现语法错误。 我希望能够看到生成的 SQL 语句，这可能会给我关于这个问题的线索。 调试时如何启用这种类型的 output？ 一般来说，我是 EF 的新手，所以对于答案，请具体明确要求。

下面是我的测试 function：

public async Task<string> FunctionHandler(string input, ILambdaContext context)
{
    try
    {

        using (var db = new loyaltyContext())
        {
            var customer = new Customer
            {
                BusinessPartnerId = 4332482,
                StoreJoined = "chadstone",
                CreatedDateTime = DateTime.Now,
                CustomerType = "STANDARD",
                DateOfBith = DateTime.Now.Date,
                StoreJoinedDate = DateTime.Now.Date,
                UpdatedDateTime = DateTime.Now,
                FirstName = "Joe",
                LastName = "Test",
                Gender = "M",
                OrganisationName = "Australian Pharmaceutical Industries"
            };

            customer.Membership.Add(new Membership { BusinessPartnerId = 4332482, DateCreated = DateTime.Now, LoyaltyCustomerId = 1234, McaId = "2701000" });
            db.Customer.Add(customer);
            var count = db.SaveChanges();
            Console.WriteLine("${count} changes");
        }
    }
    catch (Exception e)
    {
        Console.WriteLine(e.ToString());
    }

    return input?.ToUpper();
}

当前错误：

Npgsql.PostgresException (0x80004005): 42601: syntax error at end of input

   at Npgsql.NpgsqlConnector.<>c__DisplayClass160_0.<<DoReadMessage>g__ReadMessageLong|0>d.MoveNext()

--- End of stack trace from previous location where exception was thrown ---

   at Npgsql.NpgsqlConnector.<>c__DisplayClass160_0.<<DoReadMessage>g__ReadMessageLong|0>d.MoveNext() in C:\projects\npgsql\src\Npgsql\NpgsqlConnector.cs:line 973

--- End of stack trace from previous location where exception was thrown ---

   at Npgsql.NpgsqlDataReader.NextResult(Boolean async, Boolean isConsuming) in C:\projects\npgsql\src\Npgsql\NpgsqlDataReader.cs:line 407

   at Npgsql.NpgsqlDataReader.NextResult() in C:\projects\npgsql\src\Npgsql\NpgsqlDataReader.cs:line 298

   at Npgsql.NpgsqlCommand.ExecuteReaderAsync(CommandBehavior behavior, Boolean async, CancellationToken cancellationToken) in C:\projects\npgsql\src\Npgsql\NpgsqlCommand.cs:line 1195

   at Npgsql.NpgsqlCommand.ExecuteReader(CommandBehavior behavior) in C:\projects\npgsql\src\Npgsql\NpgsqlCommand.cs:line 1076

   at Npgsql.NpgsqlCommand.ExecuteReader() in C:\projects\npgsql\src\Npgsql\NpgsqlCommand.cs:line 1067

   at AWSLambdaLCSTest.Function.GetAll(NpgsqlConnection connection, String schema, String table) in C:\Users\JMatson\source\repos\AWSLambdaLCSTest\AWSLambdaLCSTest\Function.cs:line 109

   at AWSLambdaLCSTest.Function.FunctionHandler(String input, ILambdaContext context) in C:\Users\JMatson\source\repos\AWSLambdaLCSTest\AWSLambdaLCSTest\Function.cs:line 53

  Exception data:

    Severity: ERROR

    SqlState: 42601

    MessageText: syntax error at end of input

    Position: 22

    File: scan.l

    Line: 1126

    Routine: scanner_yyerror

编辑：通过按照建议尝试以下设置进行更新：

protected override void OnConfiguring(DbContextOptionsBuilder optionsBuilder)
{
    optionsBuilder.UseNpgsql("xxxxxxx").EnableSensitiveDataLogging(true);
}

但是调试 output 仍然没有显示任何内容：

Answer 1

我最近写了一篇关于这个的博客文章。 您使用的是 .net 内核吗？

https://eamonkeane.dev/how-to-view-sql-generated-by-entity-framework-core-using-logging/

在您的 startup.cs class 和 ConfigureServices 方法中启用敏感数据日志记录。

 services.AddDbContext<DutchContext>(
            cfg =>
            {
                cfg.UseSqlServer(_config.GetConnectionString("DutchConnectionString")).EnableSensitiveDataLogging();
            }
            );

接下来配置日志记录级别以将 ef 包含在您的配置文件中。 通常是appsettings.json

"Logging": {
    "LogLevel": {
        "Default": "Information",
        "Microsoft": "Warning",
        "Microsoft.EntityFrameworkCore.Database.Command": "Information"
    }
}

Now run the application and you can view the sql in your output window if you select the web server as source of the output.

output window 示例