如何编辑此 mySQL 以便将相同 id 的行合并为 1 而不是 3？

Question

The following mySQL query gets data from 2 tables, alerts_data and alerts_list . The first table has the data of an alert, and the second has the description of the alert. So in the alerts_data there are multiple rows with the same alerts_data_id that is the same with the alerts_id of alerts_list .

What i want to achieve, is to display something like this

alert number 51, 5 clicked , 2 closed
alert number 57, 13 clicked, 3 closed, 8 waiting

using mySQL or PHP (i do not know if i can get this through plain mySQL)

So for now with my knowledge I can not display the data of alert 51 in one row, but because of the different alerts_data_status i have to show 3 rows for each.

How can I do it as above?

SELECT COUNT( alerts_data_id ) AS total, alerts_data_id, alerts_data_status, alerts_list.alerts_title
FROM  alerts_data 
JOIN alerts_list ON 
alerts_data.alerts_data_id = alerts_list.alerts_id
GROUP BY alerts_data_id, alerts_data_status

//output

total - alerts_data_id - alerts_data_status - alerts_title
5     -     51 - clicked - alert number 51
2     -     52 - closed - alert number 51
13    -     57 - clicked - alert number 57
3     -     57 - waiting - alert number 57
8     -     57 waiting - alert number 57

Note: the alerts number are just examples, it can be any number

// alert_data

id - alerts_data_id - alerts_data_status

// alerts_list

alerts_id - alerts_name - alerts_text

Here's a sqlfiddle: http://sqlfiddle.com/#!9/c70c2/1

Answer 1

This may be an application for GROUP_CONCAT() .

You first want a summary of your alerts by alerts_data_id and alerts_data_status. This is a little complex, because your sqlfiddle has a whole bunch of empty alerts_data_status strings. Here, I'm replacing those empty strings with `?'. ( http://sqlfiddle.com/#!9/c70c2/23/0 )

                      SELECT COUNT(*) AS alerts_count, 
                             alerts_data_id, 
                             CASE WHEN LENGTH(alerts_data_status) = 0 THEN '?'
                                  ELSE alerts_data_status END  AS alerts_data_status
                        FROM alerts_data
                       GROUP BY alerts_data_id, alerts_data_status

You then want to roll that up inside another query

SELECT SUM(a.alerts_count) total,
       a.alerts_data_id, b. alerts_name,
       GROUP_CONCAT( CONCAT(a.alerts_count, ': ', a.alerts_data_status)
                     ORDER BY a.alerts_data_status
                     SEPARATOR "; " ) detail
  FROM (
                      SELECT COUNT(*) AS alerts_count, 
                             alerts_data_id, 
                             CASE WHEN LENGTH(alerts_data_status) = 0 THEN '?'
                                  ELSE alerts_data_status END  AS alerts_data_status
                        FROM alerts_data
                       GROUP BY alerts_data_id, alerts_data_status
       ) a
  JOIN alerts_list b ON a.alerts_data_id = b.alerts_id
 GROUP BY a.alerts_data_id, b.alerts_name

This will give you one row for each distinct alerts_data_id. Each alert is identified by its count, its id, and its name. ( http://sqlfiddle.com/#!9/c70c2/26/0 )

Then the row will contain a semicolon-separated list of the counts of the different alert status.

Answer 2

If i understand you well i think here is what you need;

SELECT 
  COUNT( alerts_data.id ) AS total, 
  ad.id,
  (SELECT count(*) from alert_list al where al.alerts_id=ad.id and alerts_data_status='clicked') as clicked,
  (SELECT count(*) from alert_list al where al.alerts_id=ad.id and alerts_data_status='closed') as closed,
  (SELECT count(*) from alert_list al where al.alerts_id=ad.id and alerts_data_status='waiting') as waiting,
FROM  alerts_data ad
GROUP BY ad.id

Answer 3

Was checking other answers and your SQLFIDDLE and thought this might be a nicer approach:

SELECT alerts_list.alerts_title,
  SUM(CASE WHEN alerts_data_status = 'clicked' THEN 1 ELSE 0 END) AS clicked,
  SUM(CASE WHEN alerts_data_status = 'closed' THEN 1 ELSE 0 END) AS closed,
  SUM(CASE WHEN alerts_data_status = 'waiting' THEN 1 ELSE 0 END) AS waiting
FROM alerts_data 
JOIN alerts_list ON alerts_data.alerts_data_id = alerts_list.alerts_id
GROUP BY alerts_list.alerts_title