例一：

DELIMITER $$

DROP PROCEDURE IF EXITS cursor_example$$
CREATE PROCEDURE cursor_example()
     READS SQL DATA
BEGIN
     DECLARE l_employee_id INT;
     DECLARE l_salary NUMERIC(8,2);
     DECLARE l_department_id INT;
     DECLARE done INT DEFAULT 0;
     DECLARE cur1 CURSOR FOR SELECT employee_id, salary, department_id FROM employees;
     DECLARE CONTINUE HANDLER FOR NOT FOUND SET done=1;

     OPEN cur1;
     emp_loop: LOOP
         FETCH cur1 INTO l_employee_id, l_salary, l_department_id;
         IF done=1 THEN
             LEAVE emp_loop;
         END IF;
     END LOOP emp_loop;
     CLOSE cur1;
END$$
DELIMITER ;

例二：

DELIMITER //
DROP PROCEDURE IF EXISTS test //
CREATE PROCEDURE test()
BEGIN
    DECLARE done INT DEFAULT 0;
    DECLARE a VARCHAR(200) DEFAULT '';
    DECLARE c VARCHAR(200) DEFAULT '';

    DECLARE mycursor CURSOR FOR SELECT  fusername FROM uchome_friend;
    DECLARE CONTINUE HANDLER FOR NOT FOUND SET done=1;

    OPEN mycursor;

    REPEAT
        FETCH mycursor INTO a;
        IF NOT done THEN
            SET c=CONCAT(c,a);/*字符串相加*/
        END IF;

    UNTIL done END REPEAT;

    CLOSE mycursor;

    SELECT c;
END //
DELIMITER ;

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mySQL 中的游标简单使用

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