DECLARE done INT DEFAULT FALSE; DECLARE a CHAR(16); DECLARE b,c INT; DECLARE cur1 CURSOR FOR SELECT id,data FROM test.t1; DECLARE cur2 CURSOR FOR SELECT i FROM test.t2; DECLARE CONTINUE HANDLER FOR NOT FOUND SET done= TRUE; OPEN cur1; OPEN cur2;read_loop:LOOP FETCH cur1 INTO a,...
DELIMITER // CREATE PROCEDURE `proc_CURSOR` (OUT param1 INT) BEGIN DECLARE a, b, c INT; DECLARE cur1 CURSOR FOR SELECT col1 FROM table1; DECLARE CONTINUE HANDLER FOR NOT FOUND SET b = 1; OPEN cur1; SET b = 0; SET c = 0; WHILE b = 0 DO FETCH cur1 INTO a; IF b = 0 ...
DECLARE v_idint; DECLARE v_dept_idint; DECLARE cur1 CURSOR FOR SELECT id,name,dept_id FROM teacher; DECLARE CONTINUE HANDLER FOR NOT FOUND SET done=false; open cur1; fetch cur1 into v_id,v_name,v_dept_id;whiledonedoselectv_id,v_name,v_dept_id;select'row---'abc; fetch cur1 i...
DECLARE cur CURSOR FOR SELECT name FROM employees; -- 声明NOT FOUND处理程序,当游标中没有更多行时,将done设置为1 DECLARE CONTINUE HANDLER FOR NOT FOUND SET done = 1; -- 打开游标 OPEN cur; -- 循环遍历游标中的所有行 read_loop: LOOP FETCH cur INTO emp_name; -- 检查是否还有更多的行 IF ...
DECLARE v_dept_idint; DECLARE cur1 CURSOR FORSELECT id,name FROM teacherwhere id>=2;DECLARE CONTINUE HANDLER FOR NOT FOUND SET done=false; open cur1;whiledonedofetch cur1 into v_id,v_name;selectv_id,v_name;select'row---'abc; endwhile; end...
在MySQL中,游标(Cursor)是一种数据库对象,用于从结果集中逐行检索数据。它允许你在查询结果上执行迭代操作,每次处理一行数据。DECLARE CURSOR语句用于声明一个游标,并定义其要使用的SQL查询。 一、游标的定义 游标是一种数据库对象,用于存储从SQL查询返回的结果集,并允许你从结果集中逐行访问数据。游标提供了一种在结...
DECLARE v_done1 int DEFAULT FALSE; /*创建游标*/ DECLARE cur_test1 CURSOR FOR SELECT a FROM test2; /*设置游标结束时v_done1的值为true,可以v_done1来判断游标cur_test1是否结束 了*/ DECLARE CONTINUE HANDLER FOR NOT FOUND SET v_done1=TRUE; /*打开游标*/ ...
DECLARE cur_score CURSOR FOR SELECT stu_id,grade FROM score; 2.2 打开游标 打开游标的语法如下: OPEN cursor_name 当我们定义好游标之后,如果想要使用游标,必须先打开游标。打开游标的时候 SELECT 语句的查询结果集就会送到游标工作区,为后面游标的逐条读取结果集中的记录做准备. open cur_score; 2.3 使用...
DELIMITER // CREATE PROCEDURE process_data() BEGIN DECLARE done INT DEFAULT FALSE; DECLARE v_id INT; DECLARE v_name VARCHAR(255); DECLARE cur CURSOR FOR SELECT id, name FROM your_table; DECLARE CONTINUE HANDLER FOR NOT FOUND SET done = TRUE; OPEN cur; read_loop: LOOP FETCH cur INTO v...
1 题目：存储过程中使用光标，把age<=10的数据age-1,age>10的数据age-2CREATE PROCEDURE test_cursor ()#定义存储过程BEGIN #开始DECLARE animal_id INT (11);#定义变量参数DECLARE animal_age INT (11);#定义变量参数DECLARE cur CURSOR FOR SELECT id,age FROM test_10;#定义光标，注意CURSOROPEN cur;#...