When I am looking for a forum post related to SQL Server, one of the junior professional is asking how to use a DO…WHILE loop is MS SQL Server. Several people wrote their opinion related to it. Everyone is saying to use WHILE loop and some of them suggesting with T-SQL structure of CURSOR with WHILE LOOP.
Obviously, when a junior professional is learning MS SQL server, the question in mind arises: is there DO… WHILE, REPEAT … UNTIL loop present in MS SQL Server as there is in C or C++ etc?
No one is answering directly on the forum whether we can use DO… WHILE or REPEAT … UNTIL in MS SQL Server or NOT. If yes, how can we implement them?
DO… WHILE in MS SQL Sever
First we look at the algorithm of DO… WHILE.
SET X = 1 DO PRINT X SET X = X + 1 WHILE X <= 10
Now we try to implement it in MS SQL Server.
DECLARE @X INT=1; WAY: --> Here the DO statement PRINT @X; SET @X += 1; IF @X<=10 GOTO WAY; --> Here the WHILE @X<=1
First we look at the algorithm of REPEAT... UNTIL
SET X = 1 REPEAT PRINT X SET X = X + 1 UNTIL X > 10
Now we try to implement it in MS SQL Server
DECLARE @X INT = 1; WAY: -- Here the REPEAT statement PRINT @X; SET @X += 1; IFNOT(@X >1 0) GOTO WAY; -- Here the UNTIL @X>10
So we see that it is possible, but a little complicated… So most developers prefer the WHILE loop in MS SQL Server.