MySQL数据库中varchar类型的数字比较大小的方法

-- ----------------------------
-- Table structure for check_test
-- ----------------------------
DROP TABLE IF EXISTS `check_test`;
CREATE TABLE `check_test` (
  `id` int(11) NOT NULL AUTO_INCREMENT,
  `current_price` varchar(10) NOT NULL,
  `price` varchar(10) NOT NULL,
  PRIMARY KEY (`id`)
) ENGINE=InnoDB AUTO_INCREMENT=9 DEFAULT CHARSET=utf8;
 
-- ----------------------------
-- Records of check_test
-- ----------------------------
INSERT INTO `check_test` VALUES ('1', '12', '14');
INSERT INTO `check_test` VALUES ('2', '22', '33');
INSERT INTO `check_test` VALUES ('3', '15', '8');
INSERT INTO `check_test` VALUES ('4', '9', '7');
INSERT INTO `check_test` VALUES ('5', '12', '12.9');

-- 找出current_price比price小的记录
select * from check_test where current_price<price;
select * from check_test where (current_price+0)<(price+0);
 
-- 找出current_price比price大的记录
select * from check_test where current_price>price;
select * from check_test where (current_price+0)>(price+0);

var current_price = "12";
var price = "14";
console.log(current_price < price);// true
 
var current_price = "15";
var price = "8";
console.log(current_price < price);// true

var current_price = "12";
var price = "14";
console.log(parseInt(current_price) < parseInt(price));// true
 
var current_price = "15";
var price = "8";
console.log(parseInt(current_price) < parseInt(price));// false