SQL Server处理字符串常用的函数

LEFT()
SELECT LEFT('Sherman',3)

RIGHT()
SELECT RIGHT('Sherman',3)

STUFF()
SELECT STUFF('Sherman',1,7,'')
SELECT STUFF('Sherman',1,3,'Alvin')

SUBSTRING()
SUBSTRING( expression, start, length )
SELECT SUBSTRING('Sherman',5,3)

CHARINDEX()
SELECT CHARINDEX(',','Sherman,Alvin')
SELECT CHARINDEX(',','Sherman,Alvin,Chris',10)

PATINDEX()
SELECT PATINDEX('%[0-9][a-zA-Z]%','Sherman was born in 1X89')

REPLACE()
SELECT REPLACE('Sherman,Alvin',',',': ')

REVERSE()
SELECT REVERSE('Sherman,Alvin')

LTRIM()
RTRIM()
SELECT '|'+LTRIM('     Sherman      ')+'|'
SELECT '|'+RTRIM('     Sherman      ')+'|'

UPPER()
LOWER()
SELECT UPPER('sherman')
SELECT LOWER('SHERMAN')

--RECURSION [rɪˈkɜ:ʃn]
WITH TEMP AS (
SELECT 1 AS NUM
UNION ALL
SELECT NUM+1
FROM TEMP
WHERE NUM<100
)
SELECT NUM
FROM TEMP
OPTION(MAXRECURSION 0);

WITH TEMP AS (
SELECT CONVERT(DATETIME,'20130101') AS DATE
UNION ALL
SELECT DATE+1
FROM TEMP
WHERE DATE<CONVERT(DATETIME,'20190101')
)
SELECT DATE
FROM TEMP
OPTION(MAXRECURSION 0);