存储过程——入门

• 基础框架

DROP PROCEDURE IF EXISTS prc_init_student; #如果存储过程存在，先删除
DECLARE $$#定义
CREATE PROCEDURE prc_init_student;
BEGIN$$
    DECLARE v_name VARCHAR(30);
    SELECT t.'customer_name' INTO v_name FROM t_user_student_enroll t where t.enroll_id=3;
    INSERT INTO t_user_customer (customer_name)VALUES(v_name);
END$$

• 加入while循环

USE 'projectName' $$
DROP PROCEDURE IF EXISTS 'tableName' $$ #如果存储过程存在，先删除
CREATE DEFINER='root'@'%' PROCEDURE 'tableName'()
BEGIN
       DECLARE v_name VARCHAR(30);
       DECLARE v_count INT(6);
       DECLARE v_index INT(6);
       SELECT count(*) INTO v_count FROM existsTable;
       SET v_index=0;
       WHILE v_index<v_count DO
               SELECT t.'customer_name' INTO v_name FROM t_user_student_enroll t  LIMIT v_index,1;
               INSERT INTO t_user_customer (customer_name)VALUES(v_name);
               SET v_index=v_index+1;
       END WHILE;
END$$