mysql中生成时间维度表

mysql中生成时间维度表

       利用mysql常用日期函数生成时间维度表，效率最高，最简单，无需其他的一些工具支持。生成结果示例如下图：

# time span

SET @d0 = "2012-01-01";

SET @d1 = "2012-12-31";

 

SET @date = date_sub(@d0, interval 1 day);

 

# set up the time dimension table

DROP TABLE IF EXISTS time_dimension;

CREATE TABLE `time_dimension` (

  `date` date DEFAULT NULL,

  `id` int NOT NULL,

  `y` smallint DEFAULT NULL,

  `m` smallint DEFAULT NULL,

  `d` smallint DEFAULT NULL,

  `yw` smallint DEFAULT NULL,

  `w` smallint DEFAULT NULL,

  `q` smallint DEFAULT NULL,

  `wd` smallint DEFAULT NULL,

  `m_name`  char(10) DEFAULT NULL,

  `wd_name` char(10) DEFAULT NULL,

  PRIMARY KEY (`id`)

);

 

# populate the table with dates

INSERT INTO time_dimension

SELECT @date := date_add(@date, interval 1 day) as date,

    # integer ID that allowsimmediate understanding

    date_format(@date, "%Y%m%d")as id,

    year(@date) as y,

    month(@date) as m,

    day(@date) as d,

    date_format(@date, "%x")as yw,

    week(@date, 3) as w,

    quarter(@date) as q,

    weekday(@date)+1 as wd,

    monthname(@date) as m_name,

    dayname(@date) as wd_name

FROM T

WHERE date_add(@date, interval 1 day) <= @d1

ORDER BY date

;

       神秘的表T，仅仅需要有多于你需要生成日期的记录数即可。思路是从T表选择多行数据，同时生成对应的日期字段。