Question

I’m using three tables. In the first table are recorded customer questions.

  customer_id   |   question   | question_id
----------------------------------------------
       58       |   question 4 |      4
       41       |   question 5 |      5
       37       |   question 3 |      3 

In the second table are recorded comments relevant to questions from the first teble

    comment   | question_id   |  user
---------------------------------------
    comment 1 |      4        |    41  
    comment 2 |      5        |    58         
    comment 3 |      4        |    41  
    comment 4 |      5        |    58  
    comment 5 |      3        |    23  

In the third table are located data about the users of this site

    user      | status
--------------------------------
     58       |      1
     41       |      1
     37       |      0 
     23       |      0 

How can I make a query that will result as a list of the last five questions sorted by question_id and the total number of comments related to each question. These questions and comments can be only by the users with the status “1” a third table.

The result in this example should look like:

  question   | total comments  |   user
-----------------------------------------------
 question 5  |      2          |    41
 question 4  |      2          |    58    

Answer 1

I’m reasonably certain this is correct, though I don’t have the data here to validate.

SELECT questions.question, 
       count(comments.question_id) as 'total comments', 
       user.user
FROM user 
  JOIN questions on user.user = questions.customer_id
  LEFT JOIN comments on questions.question_id = comments.question_id
WHERE user.status = 1
GROUP BY comments.question_id,  questions.question, users.user
ORDER BY questions.question
LIMIT 5

The LEFT JOIN on questions will allow questions to be represented even if no comments have been left on them.

Let me know if you have any questions.