我需要MS Access 2010中的复合查询帮助。
我有一个这种结构的表:
ChoirOrder(name, category, day, h_start, h_end, ord);
其中name
和category
是ChoirOrder
的主键。 category
字段可以是A
,B
或Y
。
我需要以下列格式提取数据:
FullChoirExecution (
name,
cat_a_day,
cat_a_h_start,
cat_a_h_end,
cat_a_order,
cat_b_day,
cat_b_h_start,
cat_b_h_end,
cat_b_order,
cat_y_day,
cat_y_h_start,
cat_y_h_end,
cat_y_order
);
(每个合唱团必须出现在一行且只有一行,而name
必须是主键。)
问题是,我想在NULL
,cat_x_day
,cat_x_h_start
和cat_x_h_end
字段中获取cat_x_h_order
(其中x
可以是A
,B
或Y
)如果在原始ChoirOrder
表格中,合唱团没有任何具有该类别的行。例如,如果ChoirOrder
中的数据是:
NAME | CAT | DAY | H_START | H_END | ORD
C1 | A | 04/03/2014 | 09:00 | 10:00 | 1
C2 | A | 04/03/2014 | 10:00 | 11:00 | 2
C3 | A | 04/03/2014 | 11:00 | 12:00 | 3
C4 | A | 04/03/2014 | 12:00 | 13:00 | 4
C1 | B | 05/03/2014 | 14:00 | 15:00 | 1
C2 | B | 05/03/2014 | 15:00 | 16:00 | 2
C5 | B | 05/03/2014 | 16:00 | 17:00 | 3
C3 | Y | 06/03/2014 | 09:00 | 10:00 | 1
C5 | Y | 06/03/2014 | 10:00 | 11:00 | 2
C6 | Y | 06/03/2014 | 11:00 | 12:00 | 3
C4 | Y | 06/03/2014 | 12:00 | 13:00 | 4
结果应该是:
NAME | CAT_A_DAY | CAT_A_H_START | CAT_A_H_END | CAT_A_ORDER | CAT_B_DAY | CAT_B_H_START | CAT_B_H_END | CAT_B_ORDER | CAT_Y_DAY | CAT_Y_H_START | CAT_Y_H_END | CAT_Y_ORDER |
C1 | 04/03/2014 | 09:00 | 10:00 | 1 | 05/03/2014 | 14:00 | 15:00 | 1 | | | | |
C2 | 04/03/2014 | 10:00 | 11:00 | 2 | 05/03/2014 | 15:00 | 16:00 | 2 | | | | |
C3 | 04/03/2014 | 11:00 | 12:00 | 3 | | | | | 06/03/2014 | 09:00 | 10:00 | 1 |
C4 | 04/03/2014 | 12:00 | 13:00 | 4 | | | | | 06/03/2014 | 12:00 | 13:00 | 4 |
C5 | | | | | 05/03/2014 | 16:00 | 17:00 | 3 | 06/03/2014 | 10:00 | 11:00 | 2 |
C6 | | | | | | | | | 06/03/2014 | 11:00 | 12:00 | 3 |
(由于合唱团C1
在类别为ChoirOrder
的{{1}}中没有行,因此字段为Y
,CAT_Y_DAY
,{{1 }}和CAT_Y_H_START
设置为CAT_Y_H_END
;同样适用于其他合唱团。)
我用以下代码准备了一个两表全外连接;它的工作原理是提取CAT_Y_ORDER
类别中的所有合唱团以及只有NULL
类别的行的所有合唱团(Access 2010不支持完整的外部联接,因此我使用LEFT加入UNION RIGHT联接) :
A
但是,此查询将仅提取预期结果的一部分。我需要将它组合起来或完全重写它以包含B
类别。
我以为我可以加入
SELECT
B.[name] AS [name],
A.[day] AS [cat_a_day],
A.[h_start] AS [cat_a_h_start],
A.[h_end] AS [cat_a_h_end],
A.[ord] AS [cat_a_order],
B.[day] AS [cat_b_day],
B.[h_start] AS [cat_b_h_start],
B.[h_end] AS [cat_b_h_end],
B.[ord] AS [cat_b_order]
FROM
[ChoirOrder] AS A
LEFT OUTER JOIN
[ChoirOrder] AS B
ON
(A.[name] = B.[name])
AND (A.[category]='A' AND B.[category]='B')
UNION
SELECT
B.[name] AS [name],
A.[day] AS [cat_a_day],
A.[h_start] AS [cat_a_h_start],
A.[h_end] AS [cat_a_h_end],
A.[ord] AS [cat_a_order],
B.[day] AS [cat_b_day],
B.[h_start] AS [cat_b_h_start],
B.[h_end] AS [cat_b_h_end],
B.[ord] AS [cat_b_order]
FROM
[ChoirOrder] AS A
RIGHT OUTER JOIN
[ChoirOrder] AS B
ON
(A.[name] = B.[name])
AND (A.[category]='A' AND B.[category]='B')
WHERE A.[category] IS NULL;
在查询中,但我无法使其工作。有什么想法吗?
答案 0 :(得分:1)
以下交叉表查询似乎给出了所需的结果:
TRANSFORM First(field_value) AS v
SELECT [name]
FROM
(
SELECT
[name],
'cat_' & LCase([cat]) & '_day' AS field_name,
[day] AS field_value
FROM ChoirOrder
UNION ALL
SELECT
[name],
'cat_' & LCase([cat]) & '_h_start' AS field_name,
[h_start] AS field_value
FROM ChoirOrder
UNION ALL
SELECT
[name],
'cat_' & LCase([cat]) & '_h_end' AS field_name,
[h_end] AS field_value
FROM ChoirOrder
UNION ALL
SELECT
[name],
'cat_' & LCase([cat]) & '_order' AS field_name,
[ord] AS field_value
FROM ChoirOrder
) AS u
GROUP BY [name]
PIVOT field_name IN
(
'cat_a_day', 'cat_a_h_start', 'cat_a_h_end', 'cat_a_order',
'cat_b_day', 'cat_b_h_start', 'cat_b_h_end', 'cat_b_order',
'cat_y_day', 'cat_y_h_start', 'cat_y_h_end', 'cat_y_order'
)
它返回:
name cat_a_day cat_a_h_start cat_a_h_end cat_a_order cat_b_day cat_b_h_start cat_b_h_end cat_b_order cat_y_day cat_y_h_start cat_y_h_end cat_y_order
---- ---------- ------------- ----------- ----------- ---------- ------------- ----------- ----------- ---------- ------------- ----------- -----------
C1 2014-03-04 09:00 10:00 1 2014-03-05 14:00 15:00 1
C2 2014-03-04 10:00 11:00 2 2014-03-05 15:00 16:00 2
C3 2014-03-04 11:00 12:00 3 2014-03-06 09:00 10:00 1
C4 2014-03-04 12:00 13:00 4 2014-03-06 12:00 13:00 4
C5 2014-03-05 16:00 17:00 3 2014-03-06 10:00 11:00 2
C6 2014-03-06 11:00 12:00 3