我有一个如下表:
+----+-----+-----+
| ID | GRP | NR |
+----+-----+-----+
| 1 | 1 | 101 |
| 2 | 1 | 102 |
| 3 | 1 | 103 |
| 4 | 1 | 105 |
| 5 | 1-2 | 106 |
| 6 | 1-2 | 109 |
| 7 | 1-2 | 110 |
| 8 | 2 | 201 |
| 9 | 2 | 202 |
| 10 | 3 | 300 |
| 11 | 3 | 350 |
| 12 | 3 | 351 |
| 13 | 3 | 352 |
+----+-----+-----+
我想创建一个视图,将这个列表分组GRP
并在NR
. 是否可以动态检测序列并将其缩短为范围?就像1, 2, 3, 5
会变成1-3, 5
.
所以结果应该是这样的:
+-----+--------------------+
| GRP | NRS |
+-----+--------------------+
| 1 | 101 - 103, 105 |
| 1-2 | 106, 109 - 110 |
| 2 | 201 - 202 |
| 3 | 300, 350 - 352 |
+-----+--------------------+
我现在得到的只是连接值,所以上面的表格会变成这样:
+-----+--------------------+
| GRP | NRS |
+-----+--------------------+
| 1 | 101, 102, 103, 105 |
| 1-2 | 106, 109, 110 |
| 2 | 201, 202 |
| 3 | 300, 350, 351, 352 |
+-----+--------------------+
这是实际的声明:
DECLARE @T TABLE
(
ID INT IDENTITY(1, 1)
, GRP VARCHAR(10)
, NR INT
)
INSERT INTO @T
VALUES ('1',101),('1',102),('1',103),('1',105)
,('1-2',106),('1-2',109), ('1-2',110)
,('2',201),('2',202)
,('3',300),('3',350),('3',351),('3',352)
SELECT * FROM @T
;WITH GROUPNUMS (RN, GRP, NR, NRS) AS
(
SELECT 1, GRP, MIN(NR), CAST(MIN(NR) AS VARCHAR(MAX))
FROM @T
GROUP BY GRP
UNION ALL
SELECT CT.RN + 1, T.GRP, T.NR, CT.NRS + ', ' + CAST(T.NR AS VARCHAR(MAX))
FROM @T T
INNER JOIN GROUPNUMS CT ON CT.GRP = T.GRP
WHERE T.NR > CT.NR
)
SELECT NRS.GRP, NRS.NRS
FROM GROUPNUMS NRS
INNER JOIN (
SELECT GRP, MAX(RN) AS MRN
FROM GROUPNUMS
GROUP BY GRP
) R
ON NRS.RN = R.MRN AND NRS.GRP = R.GRP
ORDER BY NRS.GRP
谁能告诉我这样做是否容易?如果有人有想法并愿意分享,那就太好了。