Question

我在mysql中选择查询时遇到问题。我在phpMyAdmin中的表是这样的：

  ------------------------------------
  |   Date_id  |        Date         |
  ------------------------------------
  |    1       |  2014-05-13         |
  |    2       |  2014-06-04         |
  |    3       |  2014-07-09         |
  |    4       |  2014-08-13         |
  |    5       |  2014-09-12         |
  |    6       |  2014-10-15         |
  |    7       |  2014-11-19         |
  |    8       |  2014-12-10         |
  |    9       |  2015-01-14         |
  |    10      |  2015-02-11         |
  |    11      |  2015-03-10         |
  |    12      |  2015-04-15         |
  |    13      |  2015-05-12         |
  |    14      |  2015-06-12         |
  ------------------------------------

我期待的结果是这样的：

------------------------------------------------------------------------------------------
 |   Year  | Jan | Feb | Mar | April | May | June | July | Aug | Sept | Oct | Nov | Dec |
------------------------------------------------------------------------------------------
 | 2014    |     |     |     |       | 13  | 04   | 07   | 13  | 12   | 15  | 19  | 10  |
 ----------------------------------------------------------------------------------------
 | 2015    | 14  | 11  | 10  |  15   | 12  | 12   |      |     |      |     |     |     |
 ----------------------------------------------------------------------------------------

如何将查询写入select语句？

Answer 1

我认为最简单的方法是使用：

select year(`Date`) as `year`,
       max(case when month(date) = 1 then day(`date`) end) as Jan,
       max(case when month(date) = 2 then day(`date`) end) as Feb,
       max(case when month(date) = 3 then day(`date`) end) as Mar,
       max(case when month(date) = 4 then day(`date`) end) as Apr,
       max(case when month(date) = 5 then day(`date`) end) as May,
       max(case when month(date) = 6 then day(`date`) end) as Jun,
       max(case when month(date) = 7 then day(`date`) end) as Jul,
       max(case when month(date) = 8 then day(`date`) end) as Aug,
       max(case when month(date) = 9 then day(`date`) end) as Sep,
       max(case when month(date) = 10 then day(`date`) end) as Oct,
       max(case when month(date) = 11 then day(`date`) end) as Nov,
       max(case when month(date) = 12 then day(`date`) end) as Dec
from table t
group by year(date)
order by year(date)

Answer 2

 SELECT
YEAR(DATE) AS YEAR,
SUM(MONTH(DATE) = 1) AS JAN ,
SUM(MONTH(DATE) = 2) AS FEB ,
SUM(MONTH(DATE) = 3) AS MAR ,
SUM(MONTH(DATE) = 4) AS APR,
SUM(MONTH(DATE) = 5) AS MAY ,
SUM(MONTH(DATE) = 6) AS JUNE ,
SUM(MONTH(DATE) = 7) AS JULY ,
SUM(MONTH(DATE) = 8) AS AUG,
SUM(MONTH(DATE) = 9) AS SEP ,
SUM(MONTH(DATE) = 10) AS OCTOBER ,
SUM(MONTH(DATE) = 11) AS NOV ,
SUM(MONTH(DATE) = 12) AS DECE
FROM table_name
WHERE  DATE >= NOW() - INTERVAL 4 YEAR 
GROUP BY 1;

Answer 3

试试这段代码：

<?php
// to get all 2014 dates...
$year = 2014;
$sql="SELECT * FROM tableName WHERE Year(dateColumnName) = '$year'";


?>

MySQL通过按月分组一年来选择所有日期

3 个答案: