=================================================================================================================================================================
WHILE LOOP
=================================================================================================================================================================

=> LOOPS ARE USED TO EXECUTE STATEMENT/STATEMENTS REPEATEDLY MULTIPLE TIMES


WHILE CONDITION------------EITHER TRUE OR FALSE
BEGIN
STATEMENTS
END


=> THE CONDITION SHOULD RESULT IN TRUE OR FALSE
=> IF CONDITION IS TRUE THE LOOP CONTINUES
=> IF CONDITION IS FALSE THE LOOP TERMINATES


--PRINT 'HELLO WORLD'
--PRINT 'HELLO WORLD'
--PRINT 'HELLO WORLD'
--PRINT 'HELLO WORLD'
--PRINT 'HELLO WORLD'
--PRINT 'HELLO WORLD'
--PRINT 'HELLO WORLD'
--PRINT 'HELLO WORLD'
--PRINT 'HELLO WORLD'
--PRINT 'HELLO WORLD'


=> PRINT HELLO WORLD 10 TIMES

DECLARE @COUNT INT ;------INITIALIZATION OF A VARIABLE AT THE SAME TIME WE HAVE DECLARED THE VARIABLE
SET @COUNT =1 ;
WHILE @COUNT <=10-----------EXIT CONDITION,,,,,,,,,,,,,,,IN THIS CASE THIS CONDITION WILL ALWAYS TRUE AND THAT IS WHY IT IS NOT GOING TO BE EXIT
BEGIN
PRINT 'HELLO WORLD'---------------------------INFINITE LOOP
SET @COUNT = @COUNT + 1------------
END


NOTE ===> ENSURE TO MENTION A STATEMENT WHICH CAN CAUSE CONDITION TO BECOME FALSE
         AS PER YOUR REQUIREMENT. IF CONDITION NEVER BECOMES FALSE THEN IT WILL BECOME
         AN INFINITE LOOP AND WILL NEVER TERMINATE.

=> WRITE A PROGRAM TO PRINT NUMBERS FROM 1 TO 10

DECLARE @I INT = 1
WHILE @I<=10-----------------EXIT CONDITION FOR THE LOOP
BEGIN
PRINT @I
SET @I = @I+1
END;

=> WRITE A PROGRAM TO PRINT 1,2,3,4,5,7,8,9,10

CONTINUE --- THIS STATEMENT IS USED TO SKIP CURRENT ITERATION OR TO SKIP THE STATEMENTS 
         --- MENTIONED AFTER THE CONTINUE FOR THE CURRENT ITERATION.
=================================================================================================================================================================

--WRONG---- INFINITE LOOP
DECLARE @I INT = 1
WHILE @I<=10
BEGIN
IF @I=6 -------------------@I=1,  @I=2  ,@I=5,,,,,6=6
CONTINUE
PRINT @I
SET @I = @I+1
END

1
2
3
4
5




--CORRECT------------
DECLARE @I INT = 0 
WHILE @I<10 
BEGIN
SET @I = @I+1
IF @I=6  
BEGIN
CONTINUE
END
print @I
END

=================================================================================================================================================================
BREAK STATEMENT -- THIS STATEMENT IS USED TO GET OUT OF LOOP AS PER OUR REQUIREMENT
                -- THIS STATEMENT EXIT THE WHILE LOOP IMMEDIATELY WHEN BREAK STATEMENT 
                -- IS ENCOUNTERED.

=> GET OUT OF THE LOOP AFTER 5

DECLARE @I INT =1
WHILE @I<=10
BEGIN
PRINT @i
IF @I = 5
BEGIN
BREAK
END
SET @I = @I+1
END

===RESULT:
1
2
3
4
5
==================================================================================================================================================================
WRITE A PROGRAM TO INPUT STRING AND PRINT IN FOLLOWING PATTERN
NAME --'HARSHIT'
EXPECTED --OUTPUT
H
A
R
S
H
I
T

--SELECT LEN('HARSHIT')
--7

HARSHIT
HARSHIT
HARSHIT
HARSHIT
HARSHIT
HARSHIT
HARSHIT
		                 STARTING POSITION,NO OF CHARATERS FROM THE STARTING POSITION
SELECT SUBSTRING('HARSHIT',1,1)
H
SELECT SUBSTRING('HARSHIT',2,1)
A
SELECT SUBSTRING('HARSHIT',3,1)
R

Completion time: 2024-09-10T10:30:27.4373034+05:30


DECLARE @S VARCHAR(20), @X INT = 1
SET @S = 'HARSHIT'
WHILE @X <= LEN(@S)----SPECIFY SOME EXIT CONDITION , 1<=7,,,2<=7
BEGIN
PRINT ' '
PRINT SUBSTRING('HARSHIT',@X,1)
SET @X = @X+1
END

 
H
 
A
 
R
 
S
 
H
 
I
 
T

Completion time: 2024-09-10T10:38:12.2343957+05:30

Completion time: 2024-09-10T10:36:44.3097805+05:30

DECLARE @S VARCHAR(20), @X INT = 1
SET @S = 'HARSHIT'
WHILE @X <= LEN(@S)
BEGIN
PRINT SUBSTRING(LEFT('HARSHIT',@X),@X,1)
SET @X = @X+1
END


==================================================================================================================================================================
WRITE A PROGRAM TO INPUT STRING AND PRINT IN FOLLOWING PATTERN
NAME --'HARSHIT'
EXPECTED --OUTPUT

H
HA
HAR
HARS
HARSH
HARSHI
HARSHIT


DECLARE @S VARCHAR(20), @X INT = 1
SET @S = 'HARSHIT'
WHILE @X <= LEN(@S)----SPECIFY SOME EXIT CONDITION , 1<=7,,,2<=7
BEGIN
PRINT SUBSTRING('HARSHIT',1,@X)
SET @X = @X+1
END

==================================================================================================================================================================
DECLARE @S VARCHAR(20), @X INT = 1
SET @S = 'HARSHIT'
WHILE @X <= LEN(@S)
BEGIN
PRINT SUBSTRING('HARSHIT',1,@X)
SET @X = @X+1
END

==================================================================================================================================================================
DECLARE @S VARCHAR(20), @X INT = 1
SET @S = 'HARSHIT'
WHILE @X <= LEN(@S)
BEGIN
PRINT SUBSTRING(LEFT('HARSHIT',@X),@X,1)
SET @X = @X+1
END


---------------------------PRINT THE HARSHIT IN THE REVERSE ORDER 1 CHARACTER PER LINE
==================================================================================================================================================================
T
I
H
S
R
A
H

SELECT RIGHT('HARSHIT',4)

T
IT
HIT
SHIT

DECLARE @S VARCHAR(20), @X INT = 1
SET @S = 'HARSHIT'
WHILE @X <= LEN(@S)
BEGIN
PRINT SUBSTRING(RIGHT('HARSHIT',@X),1,1)
SET @X = @X+1
END

------------------------------------------------------------------------------------------------------------------------------------------------------------------
T
IT
HIT
SHIT
RSHIT
ARSHIT
HARSHIT

DECLARE @S VARCHAR(20), @X INT = 1
SET @S = 'HARSHIT'
WHILE @X <= LEN(@S)
BEGIN
PRINT RIGHT('HARSHIT',@X)
SET @X = @X+1
END

==================================================================================================================================================================
==================================================================================================================================================================
PROGRAM TO PRINT FOLLOWING PATTERN
*
**
***
****
*****

SELECT REPLICATE('*',3)

***
****
*****


DECLARE @X INT = 1
WHILE @X <= 5
BEGIN
PRINT REPLICATE('*',@X)
SET @X = @X+1
END

======================================================================================================================================================================================
*****
****
***
**
*

DECLARE @X INT = 5
WHILE @X >= 1
BEGIN
PRINT REPLICATE('*',@X)
SET @X = @X-1
END

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