SQL字符串数组操作(转)
/*
一、按指定符号分割字符串，返回分割后的元素个数，方法很简单，就是看字符串中存在多少个分隔符号，然后再加一，就是要求的结果。
--Alter function Get_StrArrayLength
create function Get_StrArrayLength
(
@str varchar(5000), --要分割的字符串
@split varchar(10) --分隔符号
)
returns int
as
begin
declare @location int
declare @start int
declare @length int
set @str=ltrim(rtrim(@str))
set @location=charindex(@split,@str)
set @length=1
while @location<>0
begin
set @start=@location+1
set @location=charindex(@split,@str,@start)
set @length=@length+1
end
return @length
end
(
@str varchar(5000), --要分割的字符串
@split varchar(10) --分隔符号
)
returns int
as
begin
declare @location int
declare @start int
declare @length int
set @str=ltrim(rtrim(@str))
set @location=charindex(@split,@str)
set @length=1
while @location<>0
begin
set @start=@location+1
set @location=charindex(@split,@str,@start)
set @length=@length+1
end
return @length
end
调用示例：select dbo.Get_StrArrayLength('1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,27,28,29,30,31,32,33,34,35,
36,37,38,39,40,41,42,43,44,45,46,47,48',',')
返回值：48
二、按指定符号分割字符串，返回分割后指定索引的第几个元素，象数组一样方便
--alter function Get_StrArrayStrOfIndex
create function Get_StrArrayStrOfIndex
(
@str varchar(5000), --要分割的字符串
@split varchar(10), --分隔符号
@index int --取第几个元素
)
returns varchar(5000)
as
begin
declare @location int
declare @start int
declare @next int
declare @seed int
set @str=ltrim(rtrim(@str))
set @start=1
set @next=1
set @seed=len(@split)
set @location=charindex(@split,@str)
while @location<>0 and @index>@next
begin
set @start=@location+@seed
set @location=charindex(@split,@str,@start)
set @next=@next+1
end
if @location =0 select @location =len(@str)+1
--这儿存在两种情况：1、字符串不存在分隔符号 2、字符串中存在分隔符号，跳出while循环后，@location为0，那默认为字符串后边有一个分隔符号。
return substring(@str,@start,@location-@start)
end
(
@str varchar(5000), --要分割的字符串
@split varchar(10), --分隔符号
@index int --取第几个元素
)
returns varchar(5000)
as
begin
declare @location int
declare @start int
declare @next int
declare @seed int
set @str=ltrim(rtrim(@str))
set @start=1
set @next=1
set @seed=len(@split)
set @location=charindex(@split,@str)
while @location<>0 and @index>@next
begin
set @start=@location+@seed
set @location=charindex(@split,@str,@start)
set @next=@next+1
end
if @location =0 select @location =len(@str)+1
--这儿存在两种情况：1、字符串不存在分隔符号 2、字符串中存在分隔符号，跳出while循环后，@location为0，那默认为字符串后边有一个分隔符号。
return substring(@str,@start,@location-@start)
end
调用示例：select dbo.Get_StrArrayStrOfIndex('8,9,4',',',2)
返回值：9
三、结合上边两个函数，象数组一样遍历字符串中的元素
declare @str varchar(5000)
set @str='1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,27,28,29,30,31,32,33,34,35,36,37,38,39,40,41,42,43,44,45,46,47,48'
print dbo.Get_StrArrayLength(@str,',')
declare @next int
set @next=1
while @next<=dbo.Get_StrArrayLength(@str,',')
begin
print dbo.Get_StrArrayStrOfIndex(@str,',',@next) ----输出数组中的值
set @next=@next+1
end
set @str='1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,27,28,29,30,31,32,33,34,35,36,37,38,39,40,41,42,43,44,45,46,47,48'
print dbo.Get_StrArrayLength(@str,',')
declare @next int
set @next=1
while @next<=dbo.Get_StrArrayLength(@str,',')
begin
print dbo.Get_StrArrayStrOfIndex(@str,',',@next) ----输出数组中的值
set @next=@next+1
end
调用结果：
1
2
3
4
5
四、自己加一个函数，检查一个元素是否在数组中
Alter function CheckStrInArr(@s as varchar(50),@sArr as varchar(5000)) returns int
as
begin
declare @str varchar(5000)
set @str=@sArr
declare @next int
declare @ret int
set @ret=0
set @next=1
while @next<=dbo.Get_StrArrayLength(@str,',')
begin
if dbo.Get_StrArrayStrOfIndex(@str,',',@next)=@s
begin
set @ret=1;
end
set @next=@next+1
end
return @ret
end
as
begin
declare @str varchar(5000)
set @str=@sArr
declare @next int
declare @ret int
set @ret=0
set @next=1
while @next<=dbo.Get_StrArrayLength(@str,',')
begin
if dbo.Get_StrArrayStrOfIndex(@str,',',@next)=@s
begin
set @ret=1;
end
set @next=@next+1
end
return @ret
end
