MySQL学习笔记：生成时间维度表

# ---- 对应时间戳怎么生成的？ ----

/*
TIME_CD TIME_CD1
000000 000005
000001 000005
000002 000005
000003 000005
000004 000005
000005 000010
*/

　　利用MySQL常用日期函数生成时间维度表

• 日期时间函数
• 按小时、按分钟、按秒生成

SELECT STR_TO_DATE('September 02, 2016','%M %d, %Y') AS DATE; # 2016-09-02

SELECT CURRENT_DATE(), CURRENT_TIME(), CURRENT_TIMESTAMP;
# 2018-05-29    01:00:54     2018-05-29 01:00:54

　　MySQL快速生成时间维度表

SET @d0 = '2018-01-01';
SET @d1 = '2018-12-31';
SET @date = DATE_SUB(@d0, INTERVAL 1 DAY);

USE test;

CREATE TABLE aa_time_dim(
 DATE DATE DEFAULT NULL,
 id INT(11) NOT NULL,
 Y SMALLINT(6) DEFAULT NULL,
 m SMALLINT(6) DEFAULT NULL,
 d SMALLINT(6) DEFAULT NULL,
 yw SMALLINT(6) DEFAULT NULL,
 w SMALLINT(6) DEFAULT NULL,
 q SMALLINT(6) DEFAULT NULL,
 wd SMALLINT(6) DEFAULT NULL,
 m_name CHAR(10) DEFAULT NULL,
 wd_name CHAR(10) DEFAULT NULL,
 PRIMARY KEY (id))ENGINE = INNODB DEFAULT CHARSET = utf8;

SELECT * FROM aa_time_dim;

INSERT INTO aa_time_dim
SELECT
    @date := DATE_ADD(@date, INTERVAL 1 DAY) AS DATE,
    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 xxx
WHERE DATE_ADD(@date,INTERVAL 1 DAY) <= @d1
ORDER BY DATE;

SELECT * FROM aa_time_dim;

DROP TABLE aa_time_dim;

　　注意：此处的表xxx，仅仅需要有多于需要生成日期的记录数即可。思路是从xxx表选择多行数据，同时生成对应的日期字段。　　

　　结果：

---

END 2018-05-29 01:15:25