stuff函数
select stuff('string1',<starting position>,<length to delete from string 1>,'string2')
示例:
select stuff('youxiaofeng',2,1,'F')
从第二个字符开始,删掉一个字符,然后用'F'代替删掉字符的位置,如果不需要删掉字符,则将<length to delete from string 1>设为0即可。
注意:如果<starting position>或<length to delete from string 1 >是负的,或者<starting position>是大于<string 1>长度的数,则STUFF函数将返回NULL,如果指令的<length to delete from string 1>长于从<starting position>位置到<string 1>结尾的字符数,此函数将<string 1 >在<starting position-1>处截断--------------------------------------------------------------------------------------------
Select stuff("abcdef",2,3,"ghijk")
go
结果:aghijk
stuff的功能:删除指定长度的字符串并在指定的起始点插入另一组字符
STUFF ( character_expression , start , length , character_expression )
character_expression :操作的字符,
start:删除和插入的起始点,
length:删除的长度,
character_expression :要插入的字符
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select patindex('%jinweida%','123jinweida54')
go
结果:4
功能:返回模式在字符串中第一次出现的位置
patindex( '%pattern%' , expression )
pattern:要查找的模式
expression:被找的字符串