查询出每一种食物的最高/低价，以及最高/低价发生在哪一天

Posted 2023-02-26 Roam-G

目录

数据结构

 要求：查询出每一种食物的最高/低价，以及最高/低价发生在哪一天 

SQL 

开始查询

执行结果

---

数据结构

 要求：查询出每一种食物的最高/低价，以及最高/低价发生在哪一天 

SQL 

/*
 Navicat Premium Data Transfer

 Source Server         : 2021
 Source Server Type    : mysql
 Source Server Version : 50726
 Source Host           : localhost:3306
 Source Schema         : db01

 Target Server Type    : MySQL
 Target Server Version : 50726
 File Encoding         : 65001

 Date: 23/10/2022 23:52:25
*/

SET NAMES utf8mb4;
SET FOREIGN_KEY_CHECKS = 0;

-- ----------------------------
-- Table structure for table
-- ----------------------------
DROP TABLE IF EXISTS `table`;
CREATE TABLE `table`  (
  `id` int(11) NOT NULL,
  `food` varchar(255) CHARACTER SET utf8 COLLATE utf8_general_ci NULL DEFAULT NULL,
  `price` decimal(10, 2) NULL DEFAULT NULL,
  `date` datetime(0) NULL DEFAULT NULL,
  PRIMARY KEY (`id`) USING BTREE
) ENGINE = MyISAM CHARACTER SET = utf8 COLLATE = utf8_general_ci ROW_FORMAT = Dynamic;

-- ----------------------------
-- Records of table
-- ----------------------------
INSERT INTO `table` VALUES (111, 'chicken', 20.00, '2022-10-19 15:04:23');
INSERT INTO `table` VALUES (112, 'chicken', 50.00, '2022-10-20 15:04:39');
INSERT INTO `table` VALUES (113, 'beef', 50.00, '2022-10-14 15:04:55');
INSERT INTO `table` VALUES (114, 'pork', 30.00, '2022-10-15 16:20:19');
INSERT INTO `table` VALUES (115, 'beef', 20.00, '2022-10-01 16:21:01');
INSERT INTO `table` VALUES (116, 'pork', 36.00, '2022-10-03 16:21:17');
INSERT INTO `table` VALUES (117, 'chicken', 25.00, '2022-10-11 23:48:34');
INSERT INTO `table` VALUES (118, 'beef', 28.00, '2022-09-23 23:48:56');
INSERT INTO `table` VALUES (119, 'pork', 54.00, '2022-09-08 23:49:22');

SET FOREIGN_KEY_CHECKS = 1;

开始查询

SELECT 
t1.food as '肉类',
min(t1.price) as '最低价格',
(
SELECT 
	min(date) 
	FROM `table` as t2 
	WHERE t2.price = min(t1.price) and t2.food = t1.food
) as '最低价格对应日期',

MAX(t1.price) as '最高价格',
(
SELECT 
	MAX(date) 
	FROM `table` as t2 
	WHERE t2.price = MAX(t1.price) and t2.food=t1.food
) as '最高价格对应的日期'

FROM `table`  AS t1

GROUP BY food

执行结果