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2208/天天乐学考试答案/MySQL练习（一）.md

@@ -114,3 +114,82 @@ SELECT @result;
 ```
 
 ### 第二套
+
+```sql
+#1 创建表
+CREATE TABLE t_booking(
+	bid CHAR(10) PRIMARY KEY,
+	rid CHAR(10) NOT NULL,
+	customerName VARCHAR(50),
+	tel VARCHAR(30),
+	btime DATE
+);
+
+#2 插入记录
+INSERT INTO t_booking()
+VALUES('b0001', 'r0002', '诸葛亮', '1821234567', '2023-10-01');
+
+#3 添加字段
+ALTER TABLE t_hotel ADD introduce VARCHAR(255);
+
+#4 更新记录
+UPDATE t_room r
+SET r.price = 500
+WHERE r.rid = 'r0003';
+
+#5 tj11
+SELECT *
+FROM t_hotel h
+WHERE h.`level` IN ('二星', '三星');
+
+#6 tj12
+SELECT h.hid, ROUND(AVG(r.price), 2)
+FROM t_hotel h, t_room r
+WHERE h.hid = r.hid
+GROUP BY h.hid;
+
+#7 子查询 + 视图
+CREATE VIEW v_hotel AS
+SELECT h.hname, r.rname, r.price
+FROM t_hotel h, t_room r
+WHERE h.hid = r.hid AND r.price =(
+	SELECT MAX(price)
+	FROM t_room
+	WHERE hid = h.hid
+);
+
+#8 触发器
+DELIMITER $$
+DROP TRIGGER IF EXISTS tri_updateInteroduce;
+CREATE TRIGGER tri_updateInteroduce
+BEFORE UPDATE ON t_hotel
+FOR EACH ROW
+BEGIN
+	IF NEW.`level` <> OLD.`level` THEN
+		IF NEW.`level` IN ('一星', '二星') THEN
+			SET NEW.introduce = '实用';
+		ELSEIF NEW.`level` IN ('三星', '四星') THEN
+			SET NEW.introduce = '豪华';
+		ELSE
+			SET NEW.introduce = '奢华';
+		END IF;
+	END IF;
+
+END $$
+DELIMITER ;
+
+#9 存储过程
+DELIMITER $$
+DROP PROCEDURE IF EXISTS pro_GetLowPrice;
+CREATE PROCEDURE pro_GetLowPrice(IN in_rname VARCHAR(30), OUT out_hname VARCHAR(30))
+BEGIN
+	SELECT h.hname INTO out_hname
+	FROM t_hotel h, t_room r
+	WHERE h.hid = r.hid AND r.rname = in_rname
+	ORDER BY r.price
+	LIMIT 1;
+
+END $$
+DELIMITER ;
+```
+