sql函数整理--StringSplit

 1 SET ANSI_NULLS ON
 2 GO
 3 SET QUOTED_IDENTIFIER ON
 4 GO
 5
 6 CREATE function [dbo].[SplitString]
 7 (
 8     @Input nvarchar(max),
 9     @Separator nvarchar(max)=‘,‘,
10     @RemoveEmptyEntries bit=1
11 )
12 returns @TABLE table
13 (
14     [Id] int identity(1,1),
15     [Value] nvarchar(max)
16 )
17 as
18 begin
19     declare @Index int, @Entry nvarchar(max)
20     set @Index = charindex(@Separator,@Input)
21
22     while (@Index>0)
23     begin
24         set @Entry=ltrim(rtrim(substring(@Input, 1, @Index-1)))
25
26         if (@RemoveEmptyEntries=0) or (@RemoveEmptyEntries=1 and @Entry<>‘‘)
27             begin
28                 insert into @TABLE([Value]) Values(@Entry)
29             end
30
31         set @Input = substring(@Input, @Index+datalength(@Separator)/2, len(@Input))
32         set @Index = charindex(@Separator, @Input)
33     end
34
35     set @Entry=ltrim(rtrim(@Input))
36     if (@RemoveEmptyEntries=0) or (@RemoveEmptyEntries=1 and @Entry<>‘‘)
37         begin
38             insert into @TABLE([Value]) Values(@Entry)
39         end
40
41     return
42 end

splitstring

1 declare @str1 varchar(max), @str2 varchar(max), @str3 varchar(max)
2
3 set @str1 = ‘1,2,3‘
4 set @str2 = ‘1###2###3‘
5 set @str3 = ‘1###2###3###‘
6
7 select [Value] from [dbo].[SplitString](@str1, ‘,‘, 1)
8 select [Value] from [dbo].[SplitString](@str2, ‘###‘, 1)
9 select [Value] from [dbo].[SplitString](@str3, ‘###‘, 0)

how to use

注释：

1.SET QUOTED_IDENTIFIER 为 ON 时，标识符可以由双引号分隔，而文字必须由单引号分隔。

 1 SET QUOTED_IDENTIFIER ON
 2
 3 SELECT * FROM "USER"  WHERE a=‘netasp‘
 4
 5 SET QUOTED_IDENTIFIER ON
 6
 7 SELECT * FROM [USER] WHERE a=‘netasp‘
 8
 9 SET QUOTED_IDENTIFIER OFF
10
11 SELECT * FROM [USER]  WHERE a="netasp"
12
13 SET QUOTED_IDENTIFIER OFF
14
15 SELECT * FROM [USER]  WHERE a= ‘ netasp‘

example

=========================================================

4个字段都是int型，需要前台把它们合成一个字段输出

 1 set ANSI_NULLS ON
 2 GO
 3 SET QUOTED_IDENTIFIER ON
 4 GO
 5 CREATE FUNCTION [dbo].[FormatLocaltionName]
 6  (
 7  @rack int,
 8  @floor int,
 9  @position int,
10  @bit int
11  )
12  returns varchar(100)
13  as
14  begin
15    declare @strRack varchar(100),@strFloor varchar(100),@strPosition varchar(100),@strBit varchar(100)
16
17    declare @strReturn varchar(100)
18
19    if(@rack<10)
20     begin
21       set @strRack=‘0‘ +convert(varchar(2),@rack)
22     end
23    else
24     set @strRack=convert(varchar(50),@rack)
25     set @strFloor=convert(varchar(2),@floor)
26
27    if(@position<10)
28     begin
29       set @strPosition=‘0‘+convert(varchar(2),@position)
30     end
31    else
32     set @strPosition=convert(varchar(50),@position)
33     set @strBit=convert(varchar(2),@bit)
34
35     set @[email protected]+‘-‘[email protected]+‘-‘[email protected]+‘-‘+@strBit
36
37     return @strReturn
38  end

标量值函数

1  select dbo.[FormatLocaltionName]([row],[floor],[line],[bit])
2  as localtionName,[row],[floor],[line],[bit] from [tes]

how to use

==================================================

聚合函数：对一组值执行计算并返回单个值

标量值函数：返回一个确定类型的标量值

表值函数：以表的形式返回一个返回值

sql函数整理--StringSplit