统计某个连续时间段内的用户具体数据的sql语句该如何写？

Question

数据库中的测试数据如下所示，

想要统计某个时间段内的用户来与没来的情况，最终展示结果如下所示：

SQL测试语句：

CREATE TABLE test (
id int(11) NOT NULL AUTO_INCREMENT,
come_date date NOT NULL COMMENT '日期',
username varchar(255) NOT NULL,
PRIMARY KEY (id),
KEY username (username)
) ENGINE=MyISAM AUTO_INCREMENT=25 DEFAULT CHARSET=utf8

INSERT INTO test VALUES (1, '2015-7-1', 'test_1');
INSERT INTO test VALUES (2, '2015-7-1', 'test_2');
INSERT INTO test VALUES (3, '2015-7-1', 'test_3');
INSERT INTO test VALUES (4, '2015-7-2', 'test_1');
INSERT INTO test VALUES (5, '2015-7-2', 'test_2');
INSERT INTO test VALUES (6, '2015-7-2', 'test_3');
INSERT INTO test VALUES (7, '2015-7-5', 'test_1');
INSERT INTO test VALUES (8, '2015-7-5', 'test_2');
INSERT INTO test VALUES (9, '2015-7-5', 'test_3');
INSERT INTO test VALUES (10, '2015-7-5', 'test_4');
INSERT INTO test VALUES (11, '2015-7-7', 'test_2');
INSERT INTO test VALUES (12, '2015-7-7', 'test_3');
INSERT INTO test VALUES (13, '2015-7-7', 'test_6');
INSERT INTO test VALUES (14, '2015-7-7', 'test_7');
INSERT INTO test VALUES (15, '2015-7-7', 'test_8');
INSERT INTO test VALUES (16, '2015-7-7', 'test_9');
INSERT INTO test VALUES (17, '2015-7-7', 'test_10');
INSERT INTO test VALUES (18, '2015-7-7', 'test_11');
INSERT INTO test VALUES (19, '2015-7-8', 'test_2');
INSERT INTO test VALUES (20, '2015-7-8', 'test_3');
INSERT INTO test VALUES (21, '2015-7-8', 'test_10');
INSERT INTO test VALUES (22, '2015-7-8', 'test_11');
INSERT INTO test VALUES (23, '2015-7-9', 'test_1');
INSERT INTO test VALUES (24, '2015-7-9', 'test_10');

Answer 1

这里面有里想要的答案：
http://blog.itpub.net/29254281/viewspace-1385638

Answer 2

这个是必须要以数据库表的形式展现吗？如果没必要的话 可以select * from from test where come_date between '2015-07-01' and '2015-07-09' 对数据取出后 用后台语言处理 比较好做
如果必须要以sql查出所需结果，select aa.username,group_concat(DAY(come_date)),sum(1) from (select come_date,username from test where come_date between '2015-07-01' and '2015-07-09') aa group by aa.username;