Question

我正在尝试从我的数据库中选择所有this is the top line of my string\nthis is the second line of the string并获取有关每个[Operation]的数据。下面是我尝试使用的SQL代码。

发生以下错误：

You tried to execute a query that does not include the specified expression 'op' as part of an aggregate function

我的SQL声明：

SELECT [op] as [Operation], Sum(count) as [Number of Breakdowns], Sum(td) as [Sum of Time Down]
FROM
(
  SELECT [Operation] as op, Count(*) as count, Sum([Time Down]) as td
  FROM tblDailyDowntimeAssy
  WHERE [Type of Maintenance] = 'Breakdown'
UNION ALL
  SELECT [Operation] as op, Count(*) as count, Sum([Time Down]) as td
  FROM tblDailyDowntimeMach
  WHERE [Type of Maintenance] = 'Breakdown'
);

注意：

如果我尝试仅使用[Operation]字段并且不重命名op，则错误仍然会发生，但只是更改“操作”。到＆＃39;操作＆＃39;

Answer 1

  SELECT [Operation], Sum(count) as [Number of Breakdowns], Sum(td) as [Sum of Time Down]
FROM
(
  SELECT [Operation], Count(*) as count, Sum([Time Down]) as td
  FROM tblDailyDowntimeAssy
  WHERE [Type of Maintenance] = 'Breakdown'
  group by [Operation]
UNION ALL
  SELECT [Operation], Count(*) as count, Sum([Time Down]) as td
  FROM tblDailyDowntimeMach
  WHERE [Type of Maintenance] = 'Breakdown'
  group by [Operation]
)
group by Operation;

当您使用聚合函数时，需要在查询中添加GROUP BY子句。

Answer 2

您需要在查询中添加group by子句

select ..... from tbl_name
group by ....

然后将该字段添加到错误

中提到的group by子句

＆＃39; FIELDNAME＆＃39;不属于聚合函数 - Access SQL

2 个答案: