我正在寻找一种在SQL Server中替换使用INSTR(...)和REPLACE(REGEXP_SUBSTR(...))oracle函数的方法。
原始Oracle:
SELECT
Name,
CASE
WHEN SUBSTR (NAME, 1, 2) = 'CG'
THEN SUBSTR (NAME,INSTR (NAME,'_',1,2)+ 1,LENGTH (NAME))
ELSE REPLACE (REGEXP_SUBSTR (NAME,'_[^_]+',1,2),'_','')
END AS OPT,
CASE
WHEN SUBSTR (NAME, 1, 2) = 'CG'
THEN SUBSTR (NAME,INSTR (NAME, '_',1,1) + 1, LENGTH (NAME))
ELSE REPLACE (REGEXP_SUBSTR (NAME,'_[^_]+',1,1),'_','')
END as Name2
已更新示例输出:
+---------------------------------+----------------------+------------------------------+
| NAME | OPT | Name2 |
+---------------------------------+----------------------+------------------------------+
| AE 344592001H 6186694 | NULL | NULL |
| AE_161038002_6044777 | 6044777 | 161038002 |
| BC_VIVS_HNB011A_1WAM | HNB011A | VIVS |
| BC_56230A_30SP | 30SP | 56230A |
| CG_3334902_NETWK_ ACTLM_3334912 | NETWK_ ACTLM_3334912 | 3334902_NETWK_ ACTLM_3334912 |
| CG_3334574_HMO1_CORACT_3334575 | HMO1_CORACT_3334575 | 3334574_HMO1_CORACT_3334575 |
| CG_3207160_POSC_1502AH_3207161 | POSC_1502AH_3207161 | 3207160_POSC_1502AH_3207161 |
| UH_141015_RHM | RHM | 141015 |
| UH_127757_RIV | RIV | 127757 |
| UH 523725 RIV | NULL | NULL |
| BS_W0055785_C500_M0005672 | C500 | W0055785 |
+---------------------------------+----------------------+------------------------------+
我试着查看charindex和patindex,但没有任何消息,我认为最初的正则表达式是我的头脑。关于如何在sql server中模仿这个逻辑的任何想法?
答案 0 :(得分:1)
MS SQL Server 2014架构设置:
WITH Names ( lvl, name, remaining, idx ) AS (
SELECT 1,
name,
name,
CHARINDEX( '_', name )
FROM table_name
UNION ALL
SELECT lvl+1,
name,
SUBSTRING(remaining,idx+1,LEN(remaining)-idx),
CASE WHEN CHARINDEX( '_', remaining, idx+1 ) = 0
THEN 0
ELSE CHARINDEX( '_', remaining, idx+1 ) - idx
END
FROM Names
WHERE idx > 0
)
SELECT Name,
MAX( CASE WHEN lvl = 3 AND ( Name LIKE 'CG%' OR idx = 0 ) THEN remaining
WHEN lvl = 3 THEN SUBSTRING( remaining, 1, idx - 1 )
END ) AS OPT,
MAX( CASE WHEN lvl = 2 AND ( Name LIKE 'CG%' OR idx = 0 ) THEN remaining
WHEN lvl = 2 THEN SUBSTRING( remaining, 1, idx - 1 )
END ) AS Name2
FROM Names
GROUP BY Name
查询1 :
| Name | OPT | Name2 |
|---------------------------------|----------------------|------------------------------|
| AE 344592001H 6186694 | (null) | (null) |
| AE_161038002_6044777 | 6044777 | 161038002 |
| BC_56230A_30SP | 30SP | 56230A |
| BC_VIVS_HNB011A_1WAM | HNB011A | VIVS |
| BS_W0055785_C500_M0005672 | C500 | W0055785 |
| CG_3207160_POSC_1502AH_3207161 | POSC_1502AH_3207161 | 3207160_POSC_1502AH_3207161 |
| CG_3334574_HMO1_CORACT_3334575 | HMO1_CORACT_3334575 | 3334574_HMO1_CORACT_3334575 |
| CG_3334902_NETWK_ ACTLM_3334912 | NETWK_ ACTLM_3334912 | 3334902_NETWK_ ACTLM_3334912 |
| UH 523725 RIV | (null) | (null) |
| UH_127757_RIV | RIV | 127757 |
| UH_141015_RHM | RHM | 141015 |
<强> Results :
CHARINDEX( expressionToFind, expressionToSerach[, startIndex] )
查询2 :
_
可用于查找单词中CHARINDEX( '_', name )
的实例。
_
会找到CHARINDEX( '_', name, CHARINDEX( '_', name ) + 1 )
的第一个实例的索引。_
会找到0
的第二个实例的索引,如果没有两个_
字符,则会返回CHARINDEX( '_', name, CHARINDEX( '_', name, CHARINDEX( '_', name ) + 1 ) + 1)
。_
会找到0
的第三个实例的索引,如果没有三个_
个字符,则会返回SUBSTRING
。将其嵌入内部选择中,您可以使用它在外部选择中获取相应的SELECT name,
CASE WHEN idx2 > idx1 AND ( Name LIKE 'CG%' OR idx3 = 0 )THEN SUBSTRING( name, idx2 + 1, LEN( name ) )
WHEN idx3 > idx2 THEN SUBSTRING( name, idx2 + 1, idx3 - idx2 - 1 )
END AS OPT,
CASE WHEN name LIKE 'CG%' THEN SUBSTRING( name, idx1 + 1, LEN( name ) )
WHEN idx2 > idx1 THEN SUBSTRING( name, idx1 + 1, idx2 - idx1 - 1 )
END AS Name2
FROM (
SELECT name,
CHARINDEX( '_', name ) AS idx1,
CHARINDEX( '_', name, CHARINDEX( '_', name ) + 1 ) AS idx2,
CHARINDEX( '_', name, CHARINDEX( '_', name, CHARINDEX( '_', name ) + 1 ) + 1 ) AS idx3
FROM table_name
) t
,如下所示:
| name | OPT | Name2 |
|---------------------------------|----------------------|------------------------------|
| AE 344592001H 6186694 | (null) | (null) |
| AE_161038002_6044777 | 6044777 | 161038002 |
| BC_VIVS_HNB011A_1WAM | HNB011A | VIVS |
| BC_56230A_30SP | 30SP | 56230A |
| CG_3334902_NETWK_ ACTLM_3334912 | NETWK_ ACTLM_3334912 | 3334902_NETWK_ ACTLM_3334912 |
| CG_3334574_HMO1_CORACT_3334575 | HMO1_CORACT_3334575 | 3334574_HMO1_CORACT_3334575 |
| CG_3207160_POSC_1502AH_3207161 | POSC_1502AH_3207161 | 3207160_POSC_1502AH_3207161 |
| UH_141015_RHM | RHM | 141015 |
| UH_127757_RIV | RIV | 127757 |
| UH 523725 RIV | (null) | (null) |
| BS_W0055785_C500_M0005672 | C500 | W0055785 |
<强> Results :
{{1}}