MS Access：在两个表中查找具有不同字段的行

Question

在MS Access中：

我正在尝试将两个表与：

- TABLE1.docnumb1 = TABLE2.docnumb2
- looking for: TABLE1.sum <> TABLE2.sum2

但是查询检索到一个错误：from子句中的语法错误（或在创建左联接时出现错误，提示不支持JOIN）：

SELECT docnumb1, sum 
FROM Table1
JOIN Table2 ON docnumb1 = docnumb2;

如何查询具有不同值的行？

Answer 1

使用左联接

public static void Main(string[] args)
{
      //CreateWebHostBuilder(args).Build().Run();
      var host = CreateWebHostBuilder(args).Build();
      using (var scope = host.Services.CreateScope())
      {
            var services = scope.ServiceProvider;
            try
            {
                  var context = services.GetRequiredService<AppDbContext>();
                  //context.Database.EnsureCreated();
                  DbInitializer.Initialize(context);
            }
            catch (Exception ex)
            {
                  var logger = services.GetRequiredService<ILogger<Program>>();
                  logger.LogError(ex, "An error occurred creating the DB.");
            }
      }
      host.Run();
}

Answer 2

寻找样品（图片） 您可以比较子查询的总和

    select  t1.rownumb, t1.sum1 -t2.sum2 
    from  (
    SELECT rownumb, sum(value)  sum1 
    FROM Table1 
    group by rownumb
    ) t1 
    INNER JOIN 
     (
    SELECT rownumb, sum(value)  sum2 
    FROM Table2 
    group by rownumb
    ) t2 ON t1.rownumb = t2.rownumb and  (t1.sum1 -t2.sum2 ) <> 0