Solved

Join three tables mySQL

Posted on 2011-03-11
2
307 Views
Last Modified: 2012-05-11
I want to join three tables: anestheticrecord, patient and anesthmedsgiven

anestheticrecord and patient share the field 'PatNum'
anestheticrecord and anesthmedsgiven share the field 'AnestheticRecordNum'

I've tried the following:

SELECT anestheticrecord.AnestheticRecordNum,anestheticrecord.AnestheticDate,
patient.PatNum as 'Patient #',patient.LName,patient.FName,patient.Gender,patient.Birthdate,patient.Address,patient.Address2,patient.City,patient.Zip,
patient.HmPhone,patient.WirelessPhone,anesthmedsgiven.AnesthMedName,anesthmedsgiven.QtyGiven,anesthmedsgiven.QtyWasted
FROM anestheticrecord,patient,anesthmedsgiven
WHERE ((anestheticrecord.PatNum = patient.PatNum) AND (anesthmedsgiven.AnestheticRecordNum = anestheticrecord.AnestheticRecordNum))
AND DATE_FORMAT(anestheticdate,'%Y-%m-%d') >= '2011-01-01' AND DATE_FORMAT(anestheticdate,'%Y-%m-%d') <= '2011-03-11'

which returns no results. I don't think I can use 2 LEFT JOINS because the three tables don't share a foreign key.

Any suggestions?
0
Comment
Question by:wjstarck
2 Comments
 
LVL 1

Accepted Solution

by:
DrivingInstructor earned 500 total points
ID: 35113940
It is quite possible to use 2 left joins for this. The first left join uses the shared key between anestheticrecord and patient while the second left join uses the shared key between anestheticrecord and anesthmedsgiven thus:

 
SELECT * FROM anestheticrecord AS a
LEFT JOIN patient AS p (p.PatNum = a.PatNum)
LEFT JOIN anesthmedsgiven AS m (m.AnestheticRecordNum = a.AnestheticRecordNum)

Open in new window


May not seem real, and may break best practices, I don't know, but I know it can be done as I have done it.
0
 

Author Closing Comment

by:wjstarck
ID: 35113994
Yes, that does work after all. Thanks.
0

Featured Post

Windows Server 2016: All you need to know

Learn about Hyper-V features that increase functionality and usability of Microsoft Windows Server 2016. Also, throughout this eBook, you’ll find some basic PowerShell examples that will help you leverage the scripts in your environments!

Question has a verified solution.

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

I use MySQL for many of my development projects in a Windows environment. To manage my databases (and perform queries) for years I used a tool called MySQL administrator.  This tool has since been replaced by MySQL Workbench. So I decided to m…
Creating and Managing Databases with phpMyAdmin in cPanel.
This video shows how to use Hyena, from SystemTools Software, to bulk import 100 user accounts from an external text file. View in 1080p for best video quality.
Established in 1997, Technology Architects has become one of the most reputable technology solutions companies in the country. TA have been providing businesses with cost effective state-of-the-art solutions and unparalleled service that is designed…

773 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