sql 语句 求解救 太深了,我不知道,我只是想知道能不能用sql语句写出来,我不想用代码写,代码写虽然也行.能不能给个注意啊!!! 解决方案 » 免费领取超大流量手机卡,每月29元包185G流量+100分钟通话, 中国电信官方发货 /*Navicat MySQL Data TransferSource Server : pp2Source Server Version : 50508Source Host : localhost:3306Source Database : test2Target Server Type : MYSQLTarget Server Version : 50508File Encoding : 65001Date: 2013-12-04 11:09:50*/SET FOREIGN_KEY_CHECKS=0;-- ------------------------------ Table structure for `tabname`-- ----------------------------DROP TABLE IF EXISTS `tabname`;CREATE TABLE `tabname` ( `id` int(11) NOT NULL AUTO_INCREMENT, `guid` varchar(255) NOT NULL, `time` timestamp NOT NULL DEFAULT '0000-00-00 00:00:00' ON UPDATE CURRENT_TIMESTAMP, PRIMARY KEY (`id`)) ENGINE=MyISAM AUTO_INCREMENT=7 DEFAULT CHARSET=utf8;-- ------------------------------ Records of tabname-- ----------------------------INSERT INTO `tabname` VALUES ('1', '1', '2013-12-02 10:39:25');INSERT INTO `tabname` VALUES ('2', '2', '2013-12-03 10:39:49');INSERT INTO `tabname` VALUES ('3', '3', '2013-12-03 10:42:21');INSERT INTO `tabname` VALUES ('4', '4', '2013-12-03 10:42:22');INSERT INTO `tabname` VALUES ('5', '5', '2013-12-04 10:58:36');INSERT INTO `tabname` VALUES ('6', '6', '2013-11-28 11:01:03');-- ------------------------------ Table structure for `time_fu`-- ----------------------------DROP TABLE IF EXISTS `time_fu`;CREATE TABLE `time_fu` ( `id` int(11) NOT NULL AUTO_INCREMENT, `time` timestamp NULL DEFAULT NULL ON UPDATE CURRENT_TIMESTAMP, PRIMARY KEY (`id`)) ENGINE=MyISAM AUTO_INCREMENT=4 DEFAULT CHARSET=utf8;-- ------------------------------ Records of time_fu-- ----------------------------INSERT INTO `time_fu` VALUES ('1', '2013-12-01 10:50:54');INSERT INTO `time_fu` VALUES ('2', '2013-12-02 10:51:01');INSERT INTO `time_fu` VALUES ('3', '2013-12-03 10:51:06');--------------------------------------------select count(t.guid) as guidcount,DATE_FORMAT(f.time,'%y-%m-%d') as time from tabname as t right join time_fu as f on DATE_FORMAT(t.time,'%y-%m-%d')=DATE_FORMAT(f.time,'%y-%m-%d')group by f.time;+-----------+----------+| guidcount | time |+-----------+----------+| 0 | 13-12-01 || 1 | 13-12-02 || 3 | 13-12-03 |+-----------+----------+ MySql中如何查询出当前进行会话的用户名? 出错 specified key too long / 指定的 key 太长 怎么解决 关于主动数据库的问题 mysql中文检索 怎样用ado来连接mysql? 我們現在使用mysql來開發大型圖書批發系統,不知道會有什麽問題呢? 菜的不能再菜的问题 莫名其妙的Memory fault??? 把数据从.txt文件输入mysql的问题 mysql数据库是什么 两个对应的表添加数据问题 求一个查询语句
/*
Navicat MySQL Data TransferSource Server : pp2
Source Server Version : 50508
Source Host : localhost:3306
Source Database : test2Target Server Type : MYSQL
Target Server Version : 50508
File Encoding : 65001Date: 2013-12-04 11:09:50
*/SET FOREIGN_KEY_CHECKS=0;
-- ----------------------------
-- Table structure for `tabname`
-- ----------------------------
DROP TABLE IF EXISTS `tabname`;
CREATE TABLE `tabname` (
`id` int(11) NOT NULL AUTO_INCREMENT,
`guid` varchar(255) NOT NULL,
`time` timestamp NOT NULL DEFAULT '0000-00-00 00:00:00' ON UPDATE CURRENT_TIMESTAMP,
PRIMARY KEY (`id`)
) ENGINE=MyISAM AUTO_INCREMENT=7 DEFAULT CHARSET=utf8;-- ----------------------------
-- Records of tabname
-- ----------------------------
INSERT INTO `tabname` VALUES ('1', '1', '2013-12-02 10:39:25');
INSERT INTO `tabname` VALUES ('2', '2', '2013-12-03 10:39:49');
INSERT INTO `tabname` VALUES ('3', '3', '2013-12-03 10:42:21');
INSERT INTO `tabname` VALUES ('4', '4', '2013-12-03 10:42:22');
INSERT INTO `tabname` VALUES ('5', '5', '2013-12-04 10:58:36');
INSERT INTO `tabname` VALUES ('6', '6', '2013-11-28 11:01:03');-- ----------------------------
-- Table structure for `time_fu`
-- ----------------------------
DROP TABLE IF EXISTS `time_fu`;
CREATE TABLE `time_fu` (
`id` int(11) NOT NULL AUTO_INCREMENT,
`time` timestamp NULL DEFAULT NULL ON UPDATE CURRENT_TIMESTAMP,
PRIMARY KEY (`id`)
) ENGINE=MyISAM AUTO_INCREMENT=4 DEFAULT CHARSET=utf8;-- ----------------------------
-- Records of time_fu
-- ----------------------------
INSERT INTO `time_fu` VALUES ('1', '2013-12-01 10:50:54');
INSERT INTO `time_fu` VALUES ('2', '2013-12-02 10:51:01');
INSERT INTO `time_fu` VALUES ('3', '2013-12-03 10:51:06');
--------------------------------------------select count(t.guid) as guidcount,DATE_FORMAT(f.time,'%y-%m-%d') as time
from tabname as t
right join time_fu as f
on DATE_FORMAT(t.time,'%y-%m-%d')=DATE_FORMAT(f.time,'%y-%m-%d')
group by f.time;+-----------+----------+
| guidcount | time |
+-----------+----------+
| 0 | 13-12-01 |
| 1 | 13-12-02 |
| 3 | 13-12-03 |
+-----------+----------+