存储过程测试入门案例

CREATE PROCEDURE `test`.`new_procedure` ()
BEGIN
-- 需要定义接收游标数据的变量 
  DECLARE a CHAR(16);
  -- 游标
  DECLARE cur CURSOR FOR SELECT i FROM test.t;
  -- 遍历数据结束标志
  DECLARE done INT DEFAULT FALSE;
  -- 将结束标志绑定到游标
  DECLARE CONTINUE HANDLER FOR NOT FOUND SET done = TRUE;
  -- 打开游标
  OPEN cur;
  
  -- 开始循环
  read_loop: LOOP
    -- 提取游标里的数据，这里只有一个，多个的话也一样；
    FETCH cur INTO a;-- 抓取FETCH的时候,如果cur为null(SELECT i FROM test.t),则会触发SET done = TRUE
    -- 声明结束的时候
    IF done THEN
      LEAVE read_loop;
    END IF;
    -- 这里做你想做的循环的事件

    INSERT INTO test.t VALUES (a);

  END LOOP;
  -- 关闭游标
  CLOSE cur;

END

在MySQL的存储过程中经常会看到这句话：DECLARE CONTINUE HANDLER FOR NOT FOUND。

它的含义是：若没有数据返回,程序继续,并将变量IS_FOUND设为0 ，这种情况是出现在select XX into XXX from tablename的时候发生的。

-- start by lxm
DROP PROCEDURE  IF EXISTS loan_contract_no_rule_init;
CREATE PROCEDURE loan_contract_no_rule_init()

	BEGIN
		DECLARE done INT DEFAULT 0;
		DECLARE ruleId VARCHAR(32) DEFAULT '1528655117129572354';
		DECLARE rule_detail_id_insert VARCHAR(32);
		DECLARE rule_vale_insert VARCHAR(512);
		-- 定义游标
		DECLARE cur CURSOR FOR
			SELECT rule_detail_id as rule_detail_id_insert,rule_vale as rule_vale_insert FROM trade_rule_detail_h WHERE rule_key = 'ATTACHMENT_TYPE' AND rule_detail_id IN (SELECT rule_detail_id FROM ent_trade_rule_info t WHERE
			1 = 1 AND trade_code = 'REGISTER' AND STATUS = 1 AND prod_id = 'C01P00001' AND institution_id IN ( SELECT ent_id FROM prod_cif.cif_ent_type_ext WHERE ent_type = 9 AND prod_type = '01' ));
		DECLARE CONTINUE HANDLER FOR NOT FOUND SET done = 1;
		-- 打开游标
		OPEN cur;

		-- 提取游标里的数据；
		FETCH cur INTO rule_detail_id_insert,rule_vale_insert;

		WHILE done<>1 DO
			-- 历史快照插入明细
			IF (rule_vale_insert = 'SELL_PROTOCOL') THEN
		    -- 融单协议 >初始化> 融单合同编号
			  INSERT INTO trade_rule_detail_h(id,rule_detail_id,rule_id,rule_key,rule_status,rule_vale)VALUES
			  (REPLACE(UUID(),'-',''),rule_detail_id_insert,ruleId,'LOAN_CONTRACT_NO',1,'LOAN_CONTRACT_NO');
			ELSEIF (rule_vale_insert = 'LAST_TRADE_BACK') THEN 
			  -- 最后一手贸易背景材料 > 初始化为 > 贸易合同编号
			  INSERT INTO trade_rule_detail_h(id,rule_detail_id,rule_id,rule_key,rule_status,rule_vale)VALUES
			  (REPLACE(UUID(),'-',''),rule_detail_id_insert,ruleId,'LOAN_CONTRACT_NO',1,'BACKGROUND_CONTRACT_NO');
			ELSEIF (rule_vale_insert ='SELL_PROTOCOL,LAST_TRADE_BACK') THEN	
				-- 选择了融单协议和最后一手贸易背景材料 > 初始化 > 融单合同编号
				INSERT INTO trade_rule_detail_h(id,rule_detail_id,rule_id,rule_key,rule_status,rule_vale)VALUES
			  (REPLACE(UUID(),'-',''),rule_detail_id_insert,ruleId,'LOAN_CONTRACT_NO',1,'LOAN_CONTRACT_NO');
			ELSE 
			  -- 其他无
				INSERT INTO trade_rule_detail_h(id,rule_detail_id,rule_id,rule_key,rule_status,rule_vale)VALUES
			  (REPLACE(UUID(),'-',''),rule_detail_id_insert,ruleId,'LOAN_CONTRACT_NO',1,'');
		END IF;
			FETCH cur INTO rule_detail_id_insert,rule_vale_insert;
		END WHILE;
		CLOSE cur;
	END;

CALL loan_contract_no_rule_init();

-- end by lxm