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MySQL如何填充范围内的缺失日期?

更新时间:2022-04-05 06:20:56

MySQL没有递归功能,因此您只需要使用NUMBERS表技巧-

MySQL doesn't have recursive functionality, so you're left with using the NUMBERS table trick -

  1. 创建仅包含递增数字的表-使用auto_increment易于完成:

  1. Create a table that only holds incrementing numbers - easy to do using an auto_increment:

DROP TABLE IF EXISTS `example`.`numbers`;
CREATE TABLE  `example`.`numbers` (
  `id` int(10) unsigned NOT NULL auto_increment,
   PRIMARY KEY  (`id`)
) ENGINE=InnoDB DEFAULT CHARSET=latin1;

  • 使用以下表格填充表格:

  • Populate the table using:

    INSERT INTO `example`.`numbers`
      ( `id` )
    VALUES
      ( NULL )
    

    ...根据需要提供任意数量的值.

    ...for as many values as you need.

    使用 DATE_ADD 构建日期列表,并根据NUMBERS.id值增加日期.用您各自的开始和结束日期替换"2010-06-06"和"2010-06-14"(但使用相同的格式,YYYY-MM-DD)-

    Use DATE_ADD to construct a list of dates, increasing the days based on the NUMBERS.id value. Replace "2010-06-06" and "2010-06-14" with your respective start and end dates (but use the same format, YYYY-MM-DD) -

    SELECT `x`.*
      FROM (SELECT DATE_ADD('2010-06-06', INTERVAL `n`.`id` - 1 DAY)
              FROM `numbers` `n`
             WHERE DATE_ADD('2010-06-06', INTERVAL `n`.`id` -1 DAY) <= '2010-06-14' ) x
    

  • 根据时间部分将联接左移到数据表中:

  • LEFT JOIN onto your table of data based on the time portion:

       SELECT `x`.`ts` AS `timestamp`,
              COALESCE(`y`.`score`, 0) AS `cnt`
         FROM (SELECT DATE_FORMAT(DATE_ADD('2010-06-06', INTERVAL `n`.`id` - 1 DAY), '%m/%d/%Y') AS `ts`
                 FROM `numbers` `n`
                WHERE DATE_ADD('2010-06-06', INTERVAL `n`.`id` - 1 DAY) <= '2010-06-14') x
    LEFT JOIN TABLE `y` ON STR_TO_DATE(`y`.`date`, '%d.%m.%Y') = `x`.`ts`
    

  • 如果要维护日期格式,请使用

    If you want to maintain the date format, use the DATE_FORMAT function:

    DATE_FORMAT(`x`.`ts`, '%d.%m.%Y') AS `timestamp`