Summary: in this tutorial, you will learn how to use the SQL Server BREAK statement to immediately exit a WHILE loop.
SQL Server BREAK statement overview #
In the previous tutorial, you have learned how to use the WHILE statement to create a loop. To exit the current iteration of a loop, you use the BREAK statement.
The following illustrates the typical syntax of the BREAK statement:
WHILE Boolean_expression
BEGIN
-- statements
IF condition
BREAK;
-- other statements
END
Code language: SQL (Structured Query Language) (sql)In this syntax, the BREAK statement exit the WHILE loop immediately once the condition specified in the IF statement is met. All the statements between the BREAK and END keywords are skipped.
Suppose we have a WHILE loop nested inside another WHILE loop:
WHILE Boolean_expression1
BEGIN
-- statement
WHILE Boolean_expression2
BEGIN
IF condition
BREAK;
END
END
Code language: SQL (Structured Query Language) (sql)In this case, the BREAK statement only exits the innermost loop in the WHILE statement.
Note that the BREAK statement can be used only inside the WHILE loop. The IF statement is often used with the BREAK statement but it is not required.
SQL Server BREAK statement example #
The following example illustrates how to use the BREAK statement:
DECLARE @counter INT = 0;
WHILE @counter <= 5
BEGIN
SET @counter = @counter + 1;
IF @counter = 4
BREAK;
PRINT @counter;
END
Code language: SQL (Structured Query Language) (sql)Output:
1
2
3In this example:
First, we declared a variable named @counter and set its value to zero.
Then, we used the WHILE statement to increases the @counter by one in each iteration and print out the @counter‘s value as long as the value of the @counter is less than or equal to five.
Inside the loop, we also checked if the value of @counter equals four, then we exited the loop. In the fourth iteration, the value of the counter reached 4, then the loop is terminated. Also, the PRINT statement after the BREAK statement was skipped.
In this tutorial, you have learned how to use the SQL Server BREAK statement to exit a loop immediately.