Solved

Counting a row in sql

Posted on 2009-03-30
3
269 Views
Last Modified: 2012-05-06
Hey,

I have to display a column that is a count of another row on another table. I have done it using two queries but I would like to find out how to do it in one query.

The column to display will be "Number of Exercises" and it will count the number of "Exercise Id's" on the Session Details table.

I have attached my code and the tables to help you all understand how they are related.

Thanks.
$sql = "Select Sessions.Date_Created, Sessions.Created_By
        From Sessions, Session_Details
        Where Sessions.Member_Id = '$clientID'";
    $result = mysql_query($sql);
    while ($ROW = mysql_fetch_array($result)) {
        $sessionID = $ROW['Session_Id'];
		$sessionDate = $ROW['Date_Created'];
        echo date('F d, Y',strtotime($sessionDate));
        echo $createdBy = $ROW['Created_By'];
	}
//    Retrieve the number of exercises in that session
    $sql2 = "Select Session_Details.Exercise_Id
        From Session_Details, Sessions
        Where Sessions.Member_Id = '$clientID' AND Session_Details.Session_Id = Sessions.Session_Id";
    $result2 = mysql_query($sql2);
    echo mysql_num_rows($result2);

Open in new window

tables.bmp
0
Comment
Question by:tqrecords
  • 2
3 Comments
 
LVL 142

Expert Comment

by:Guy Hengel [angelIII / a3]
ID: 24023920
you mean:
Select s.Date_Created, s.Created_By, count(sd.exercice_id) exercice_count
From Sessions s 
left join Session_Details sd
  on sd.session_id = s.session_id
Where s.Member_Id = '$clientID'
group by s.Member_id

Open in new window

0
 

Author Comment

by:tqrecords
ID: 24024294
Thanks, but there is also one more join I need to make from another table.

There is a created_by column in the Sessions table and it is an integer value.

The created_by will match the member_id on the members table and will return the name of the member.

I have the updated tables attached.


tables.bmp
0
 
LVL 142

Accepted Solution

by:
Guy Hengel [angelIII / a3] earned 500 total points
ID: 24026796
simply add a join
Select s.Date_Created, s.Created_By, count(sd.exercice_id) exercice_count
 , m.username created_by_user
From Sessions s 
left join Session_Details sd
  on sd.session_id = s.session_id
join members m
  on m.member_id = s.created_by
Where s.Member_Id = '$clientID'
group by s.Member_id

Open in new window

0

Featured Post

Optimizing Cloud Backup for Low Bandwidth

With cloud storage prices going down a growing number of SMBs start to use it for backup storage. Unfortunately, business data volume rarely fits the average Internet speed. This article provides an overview of main Internet speed challenges and reveals backup best practices.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

This article will explain how to display the first page of your Microsoft Word documents (e.g. .doc, .docx, etc...) as images in a web page programatically. I have scoured the web on a way to do this unsuccessfully. The goal is to produce something …
This article discusses four methods for overlaying images in a container on a web page
Explain concepts important to validation of email addresses with regular expressions. Applies to most languages/tools that uses regular expressions. Consider email address RFCs: Look at HTML5 form input element (with type=email) regex pattern: T…
This tutorial will teach you the core code needed to finalize the addition of a watermark to your image. The viewer will use a small PHP class to learn and create a watermark.

778 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question