Reverse integer without using REVERSE() from the table using SQL Serve

Question

How to Reverse integer without using REVERSE() from the table Suppose, i have table name Numbers and column name num which has a value of 123 how do i reverse it to 321 ? Thank YOu

Rijwan Ansari · Answer

Hi, You can do in this way DECLARE @StringToReverse VARCHAR(55) Select @StringToReverse = ColumnNameToReverse from the TableName ;WITH cte AS ( SELECT @StringToReverse AS string, CAST( '' AS VARCHAR(55)) AS revStr, LEN(@StringToReverse) AS ln UNION ALL SELECT SUBSTRING(string,0,ln) AS string, CAST(revStr + SUBSTRING(string,ln,1) AS VARCHAR(55)) AS revStr, ln-1 AS ln FROM cte WHERE ln >= 1) SELECT @StringToReverse AS String, revStr FROM cte WHERE ln = 0 Regards Rijwan

Satya Karki · Answer

Hi, Check this blog https://sqlwithmanoj.com/2011/08/18/reverse-a-string-without-using-tsqls-reverse-function/

Siddharth Gajbhiye · Answer

Hello Saroj You must create a function CREATE function StringReverse(@inputstring varchar ( max )) returns varchar ( max ) AS BEGIN DECLARE @i int , @Result varchar ( max ) SET @Result= '' SET @i = 1 WHILE @i BEGIN SET @Result = SUBSTRING (@inputstring,@i,1) + @Result SET @i=@i + 1 END RETURN @Result END Execution of function - select dbo.StringReverse('xyz123abc') Reference : https://stackoverflow.com/questions/57972660/how-do-i-reverse-a-string-in-sql-server-without-using-reverse-function

Jignesh Kumar · Answer

Hi Saroj, You can create function and use that function in select statement, CREATE function IntegerReverse(@number int ) returns int AS BEGIN DECLARE @i int , @Result int SET @Result=( SELECT (SELECT N FROM (SELECT TOP (LEN(@number)) SUBSTRING(CAST(@number AS VARCHAR(19)),N,1) FROM (VALUES(1),(2),(3),(4),(5),(6),(7),(8),(9), (10),(11),(12),(13),(14),(15),(16),(17), (18),(19))a(N) WHERE N ORDER BY N DESC) b(N) FOR XML PATH( '' ), TYPE).value( '.' , 'VARCHAR(19)' )) RETURN @Result END You can call this function as below. select dbo.IntegerReverse(num) from Numbers