mysql 日期辅助表

Posted 2022-12-01 alittlesmile

mysql 生成日期表

#1、创建一个num表，用来存储数字0~9

CREATE TABLE num (i int);
#2、在num表中生成0~9

INSERT INTO num (i) VALUES (0), (1), (2), (3), (4), (5), (6), (7), (8), (9);
#3、生成一个存储日期的表，datalist是字段名

CREATE TABLE  if not exists calendar(datelist date);
#4、生成并插入日期数据

INSERT INTO calendar(datelist) SELECT
      adddate(
          (   -- 这里的起始日期，你可以换成当前日期
              DATE_FORMAT("2016-1-1", ‘%Y-%m-%d‘) 
          ),
          numlist.id
     ) AS `date`
FROM
(
  SELECT
        n1.i + n10.i * 10 + n100.i * 100 + n1000.i * 1000+ n10000.i * 10000 AS id
        FROM
        num n1
        CROSS JOIN num AS n10
        CROSS JOIN num AS n100
        CROSS JOIN num AS n1000
        CROSS JOIN num AS n10000
     ) AS numlist;
#5、最后再添加主键即可

ALTER TABLE `calendar`
ADD COLUMN `id`  int UNSIGNED NOT NULL AUTO_INCREMENT COMMENT ‘主键‘ FIRST ,
ADD PRIMARY KEY (`id`);