获取mysql中最近6个月的值

Question

我需要从数据库中获取最近六个月的值. 这是我的小提琴.我需要动态获取值.现在二月.所以我需要八月到一月的数据库值.如果是3月那么值应自动更改为10月到2月.所以我需要获得最近六个月的价值.

我的守则如下.

CREATE TABLE IF NOT EXISTS `ratepersqft` (
  `price_id` int(11) NOT NULL auto_increment,
  `project_id` int(11) default NULL,
  `date` varchar(255) default NULL,
  `rate_per_sqft` double default NULL,
  `common_location` varchar(255) default NULL,
  PRIMARY KEY  (`price_id`)
); 

INSERT INTO `ratepersqft` (`price_id`, `project_id`, `date`, `rate_per_sqft`, `common_location`) VALUES
    (1, 1, '2012-07-01 ', 2800, 'ECR'),
    (2, 2, '2012-07-02 ', 1550, 'ECR'),
    (3, 3, '2012-07-03 ', 1850, 'ECR'),
    (4, 4, '2012-07-04 ', 4425, 'ECR'),
    (5, 5, '2012-07-05 ', 2300, 'ECR'),
    (6, 1, '2012-08-01 ', 2900, 'ECR'),
    (7, 2, '2012-08-02 ', 1650, 'ECR'),
    (8, 3, '2012-08-03 ', 1950, 'ECR'),
    (9, 4, '2012-08-04 ', 4525, 'ECR'),
    (10, 5, '2012-08-05 ', 2200, 'ECR'),
    (11, 1, '2012-09-01 ', 3000, 'ECR'),
    (12, 2, '2012-09-02 ', 1450, 'ECR'),
    (13, 3, '2012-09-03 ', 2050, 'ECR'),
    (14, 4, '2012-09-04 ', 4625, 'ECR'),
    (15, 5, '2012-09-05 ', 2100, 'ECR'),
    (16, 1, '2012-10-01 ', 3100, 'ECR'),
    (17, 2, '2012-10-02 ', 2150, 'ECR'),
    (18, 3, '2012-10-03 ', 1850, 'ECR'),
    (19, 4, '2012-10-04 ', 4725, 'ECR'),
    (20, 5, '2012-10-05 ', 1900, 'ECR'),
    (21, 1, '2012-11-01 ', 3200, 'ECR'),
    (22, 2, '2012-11-02 ', 2250, 'ECR'),
    (23, 3, '2012-11-03 ', 1850, 'ECR'),
    (24, 4, '2012-11-04 ', 4825, 'ECR'),
    (25, 5, '2012-11-05 ', 2300, 'ECR'),
    (26, 1, '2012-12-01 ', 3300, 'ECR'),
    (27, 2, '2012-12-02 ', 2350, 'ECR'),
    (28, 3, '2012-12-03 ', 1850, 'ECR'),
    (29, 4, '2012-12-04 ', 4925, 'ECR'),
    (30, 5, '2012-12-05 ', 2400, 'ECR'),
    (31, 1, '2013-01-01 ', 3400, 'ECR'),
    (32, 2, '2013-01-02 ', 2000, 'ECR'),
    (33, 3, '2013-01-03 ', 2450, 'ECR'),
    (34, 4, '2013-01-04 ', 5025, 'ECR'),
    (35, 5, '2013-01-05 ', 2500, 'ECR'),
    (36, 1, '2013-02-01 ', 3500, 'ECR'),
    (37, 2, '2013-02-02 ', 2100, 'ECR'),
    (38, 3, '2013-02-03 ', 2550, 'ECR'),
    (39, 4, '2013-02-04 ', 5125, 'ECR'),
    (40, 5, '2013-02-05 ', 2600, 'ECR'),
    (41, 1, '2012-06-01 ', 1800, 'ECR'),
    (42, 2, '2012-06-02 ', 1150, 'ECR'),
    (43, 3, '2012-06-03 ', 1350, 'ECR'),
    (44, 4, '2012-06-04 ', 3425, 'ECR'),
    (45, 5, '2012-06-05 ', 2100, 'ECR');

我正在尝试这个查询,它给了我数据库中的所有值.

SELECT *
  FROM ratepersqft
 WHERE MONTH(date) < DATE_SUB(CURDATE(), INTERVAL 6 MONTH)

希望我的问题很明确.提前致谢!!!

Answer 1

对于MYSQL:您可以使用 date_add:

 SELECT * FROM ratepersqft 
WHERE date < Now() and date > DATE_ADD(Now(), INTERVAL- 6 MONTH);

对于SQL Server:,dateadd:

  SELECT * FROM ratepersqft 
 WHERE date < Now() and date > DATEADD(Month, -6, Now());

http://www.sqlfiddle.com/#!2/1f8029/48

**请将您的日期列名称用反引号包装,因为它是一个保留的关键字.**

MYSQL更新:

SQLFIDDLE DEMO

SELECT *
FROM ratepersqft 
WHERE date_format(date,'%Y-%m') < 
                     date_format(now(),'%Y-%m')
and date_format(date,'%Y-%m') >= 
                     date_format(now() - interval 6 month,'%Y-%m')
order by date desc;