A stored procedure in which consecutive numbered serial numbers are spliced into a string.

Stored Procedure | serial number
User questions:
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Test1 table
ID Start End
1 1 5
2 6 10
3 21 25
4 26 30
5 51 60
Hope to get results:
String:1-10,21-30,51-60
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The solution of string concatenation using variable:

--Build Test table:
CREATE TABLE test1 (ID int,start int,[end] int)

--Add test data:
Insert Test1 Select 1,1,5
Union Select 2,6,10
Union Select 3,21,25
Union Select 4,26,30
Union Select 5,51,60

--a function to create a concatenation string:
CREATE PROCEDURE ProA
As
Begin

DECLARE @s varchar (8000)

--Give the variable a corresponding value in the first row of the table, cast (min (start)-1 is to be properly connected to the first line in the subsequent full table query. Note that if the serial number is starting at 0, '-' to be replaced with the other word Furu "+", the last select @s, then change back to the '-' number, the specific statement is: Select replace (@s, ' + ', '-'):
Select @s= + cast (min (start) as varchar (10)) + '-'
+ CAST (min (start)-1 as varchar (10))
From Test1

--Sequential query and concatenation of strings:
Select @s= Left (@s,len (@s)-charindex ('-', reverse (@s)) +1)
+ Case when cast (right (@s,charindex ('-', reverse (@s))-1) as int) +1
=start
Then cast ([end] as varchar (20))
else Right (@s,charindex ('-', reverse (@s))-1) + ', '
+ CAST (start as varchar (10)) + '-'
+ CAST ([end] as varchar (10))
End
From Test1
ORDER BY Start

--Returns the result:
Select @s

End

--Delete test table:
drop table Test1