MySQL count(*) 一个月内每天返回 [BLOB-2B] 而不是数字

Question

我将使用特定用户 ID(vwr_tid) 计算一个月中每天的每一行。一切正常 - 结果显示在表格中，但有一件事。每天的计数不会出现。它变成了 [BLOB-xx] 而不是当天的行数。这是我的代码:

SELECT MONTH_v, YEAR_V, 
GROUP_CONCAT(IF(day_v=1, views, null)) AS '1',
GROUP_CONCAT(IF(day_v=2, views, null)) AS '2',
GROUP_CONCAT(IF(day_v=3, views, null)) AS '3',
GROUP_CONCAT(IF(day_v=4, views, null)) AS '4',
GROUP_CONCAT(IF(day_v=5, views, null)) AS '5',
GROUP_CONCAT(IF(day_v=6, views, null)) AS '6',
GROUP_CONCAT(IF(day_v=7, views, null)) AS '7',
GROUP_CONCAT(IF(day_v=8, views, null)) AS '8',
GROUP_CONCAT(IF(day_v=9, views, null)) AS '9',
GROUP_CONCAT(IF(day_v=10, views, null)) AS '10',
GROUP_CONCAT(IF(day_v=11, views, null)) AS '11',
GROUP_CONCAT(IF(day_v=12, views, null)) AS '12',
GROUP_CONCAT(IF(day_v=13, views, null)) AS '13',
GROUP_CONCAT(IF(day_v=14, views, null)) AS '14',
GROUP_CONCAT(IF(day_v=15, views, null)) AS '15',
GROUP_CONCAT(IF(day_v=16, views, null)) AS '16',
GROUP_CONCAT(IF(day_v=17, views, null)) AS '17',
GROUP_CONCAT(IF(day_v=18, views, null)) AS '18',
GROUP_CONCAT(IF(day_v=19, views, null)) AS '19',
GROUP_CONCAT(IF(day_v=20, views, null)) AS '20',
GROUP_CONCAT(IF(day_v=21, views, null)) AS '21',
GROUP_CONCAT(IF(day_v=22, views, null)) AS '22',
GROUP_CONCAT(IF(day_v=23, views, null)) AS '23',
GROUP_CONCAT(IF(day_v=24, views, null)) AS '24',
GROUP_CONCAT(IF(day_v=25, views, null)) AS '25',
GROUP_CONCAT(IF(day_v=26, views, null)) AS '26',
GROUP_CONCAT(IF(day_v=27, views, null)) AS '27',
GROUP_CONCAT(IF(day_v=28, views, null)) AS '28',
GROUP_CONCAT(IF(day_v=29, views, null)) AS '29',
GROUP_CONCAT(IF(day_v=30, views, null)) AS '30',
GROUP_CONCAT(IF(day_v=31, views, null)) AS '31'
FROM
(
 SELECT DAY(vwr_date) AS day_v, 
 MONTH(vwr_date) AS MONTH_v, 
 Year(vwr_date) AS YEAR_V,
 date(vwr_date) AS date_v, 
 count(vwr_id) AS views 
 FROM car_viewer 
 WHERE Year(vwr_date)='2012' AND vwr_tid='18' 
 GROUP BY date_v 
) as viewz
GROUP BY MONTH_v, YEAR_V 
ORDER BY MONTH_v, YEAR_V DESC

该脚本是从@rs更新的:Count record each day of a month from mysql into html table

结果。

Answer 1

当 SUM() 可以满足您的需求时，我认为不需要 GROUP_CONCAT():

SELECT MONTH_v, YEAR_V, 
SUM(IF(day_v=1, views, 0)) AS '1',
SUM(IF(day_v=2, views, 0)) AS '2',
SUM(IF(day_v=3, views, 0)) AS '3',
SUM(IF(day_v=4, views, 0)) AS '4',
SUM(IF(day_v=5, views, 0)) AS '5',
SUM(IF(day_v=6, views, 0)) AS '6',
SUM(IF(day_v=7, views, 0)) AS '7',
SUM(IF(day_v=8, views, 0)) AS '8',
SUM(IF(day_v=9, views, 0)) AS '9',
SUM(IF(day_v=10, views, 0)) AS '10',
SUM(IF(day_v=11, views, 0)) AS '11',
SUM(IF(day_v=12, views, 0)) AS '12',
SUM(IF(day_v=13, views, 0)) AS '13',
SUM(IF(day_v=14, views, 0)) AS '14',
SUM(IF(day_v=15, views, 0)) AS '15',
SUM(IF(day_v=16, views, 0)) AS '16',
SUM(IF(day_v=17, views, 0)) AS '17',
SUM(IF(day_v=18, views, 0)) AS '18',
SUM(IF(day_v=19, views, 0)) AS '19',
SUM(IF(day_v=20, views, 0)) AS '20',
SUM(IF(day_v=21, views, 0)) AS '21',
SUM(IF(day_v=22, views, 0)) AS '22',
SUM(IF(day_v=23, views, 0)) AS '23',
SUM(IF(day_v=24, views, 0)) AS '24',
SUM(IF(day_v=25, views, 0)) AS '25',
SUM(IF(day_v=26, views, 0)) AS '26',
SUM(IF(day_v=27, views, 0)) AS '27',
SUM(IF(day_v=28, views, 0)) AS '28',
SUM(IF(day_v=29, views, 0)) AS '29',
SUM(IF(day_v=30, views, 0)) AS '30',
SUM(IF(day_v=31, views, 0)) AS '31'
FROM
(
 SELECT DAY(vwr_date) AS day_v, 
 MONTH(vwr_date) AS MONTH_v, 
 Year(vwr_date) AS YEAR_V,
 date(vwr_date) AS date_v, 
 count(vwr_id) AS views 
 FROM car_viewer 
 WHERE Year(vwr_date)='2012' AND vwr_tid='18' 
 GROUP BY date_v 
) as viewz
GROUP BY MONTH_v, YEAR_V 
ORDER BY MONTH_v, YEAR_V DESC;

参见http://sqlfiddle.com/#!2/75aa8/1一个工作示例。