Sql server® 2012 t-sql fundamentals

The 

WHILE

 Flow element

T-SQL provides the WHILE element to enable you to execute code in a loop. The WHILE element 

executes a statement or statement block repeatedly while the predicate you specify after the WHILE 

keyword is TRUE. When the predicate is FALSE or UNKNOWN, the loop terminates.

T-SQL doesn’t provide a built-in looping element that executes a predetermined number of times, 

but it’s very easy to mimic such an element with a WHILE loop and a variable. For example, the fol-

lowing code demonstrates how to write a loop that iterates 10 times.

DECLARE @i AS INT = 1; 

WHILE @i <= 10 

BEGIN 

  PRINT @i; 

  SET @i = @i + 1; 

END;

The code declares an integer variable called @i that serves as the loop counter and initializes it 

with the value 1. The code then enters a loop that iterates while the variable is smaller than or equal 

to 10. In each iteration, the code in the loop’s body prints the current value of @i and then increments 

it by 1. This code returns the following output showing that the loop iterated 10 times.

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