LOOP statement

The LOOP statement repeats the execution of a statement or a group of statements.

Syntax

Description

label: Specifies the label for the LOOP statement. If the ending label is specified, it must be the same as the beginning label. The label name cannot be the same as the routine name or another label within the same scope. For more information, see References to SQL labels.
SQL-procedure statement: Specifies an SQL statement to be executed in the loop

Notes

Considerations for the diagnostics area: At the beginning of the first iteration of the LOOP statement, and with every subsequent iteration, the diagnostics area is cleared.

Considerations for SQLSTATE and SQLCODE variables: Prior to executing the first SQL-procedure statement within that LOOP statement, the SQLSTATE and SQLCODE values reflect the last values that were set prior to the LOOP statement. If the loop is terminated with a GOTO or a LEAVE statement, the SQLSTATE and SQLCODE values reflect the successful completion of that statement. When the LOOP statement iterates, the SQLSTATE and SQLCODE values reflect the result of the last SQL statement executed within the LOOP statement.

Examples

This procedure uses a LOOP statement to fetch values from the employee table. Each time the loop iterates, the OUT parameter counter is incremented and the value of v_midinit is checked to ensure that the value is not a single space (' '). If v_midinit is a single space, the LEAVE statement passes the flow of control outside of the loop.

 CREATE PROCEDURE LOOP_UNTIL_SPACE (OUT COUNTER INTEGER)
    LANGUAGE SQL
    BEGIN
       DECLARE v_counter INTEGER DEFAULT 0;
       DECLARE v_firstnme VARCHAR(12);
       DECLARE v_midinit CHAR(1);
       DECLARE v_lastname VARCHAR(15);
       DECLARE c1 CURSOR FOR
          SELECT firstnme, midinit, lastname
          FROM employee;
       DECLARE CONTINUE HANDLER FOR NOT FOUND
          SET counter = -1;
       OPEN c1;
       fetch_loop:
       LOOP
          FETCH c1 INTO v_firstnme, v_midinit, v_lastname;
          IF v_midinit = ' ' THEN
             LEAVE fetch_loop;
          END IF;
          SET v_counter = v_counter + 1;
       END LOOP fetch_loop;
       SET counter = v_counter;
       CLOSE c1;
    END