1.创建一张表Table A,将上述数据插入表中,(字段名称自定)
CREATE TABLE `a` (
`callnumber` varchar(255) DEFAULT NULL,
`callednumber` varchar(255) DEFAULT NULL,
`callcount` varchar(255) DEFAULT NULL,
`calltime` datetime DEFAULT NULL
) ENGINE=InnoDB DEFAULT CHARSET=utf8
INSERT INTO `a` VALUES ('001', '006', '2', '2019-11-21 00:00:00');
INSERT INTO `a` VALUES ('003', '008', '4', '2019-11-25 00:00:00');
INSERT INTO `a` VALUES ('005', '007', '5', '2019-11-14 00:00:00');
INSERT INTO `a` VALUES ('006', '007', '3', '2019-10-25 00:00:00');
INSERT INTO `a` VALUES ('006',