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Multiple joins with junction tables

Posted on 2014-10-10
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Last Modified: 2014-10-20
Hi all,
I have a table listing case studies and another table that list outcomes.  A case study can have multiple outcomes so I created a junction table.
I want to run a SQL that will show the case once and each of the outcomes so far I have
SELECT caseSummaries.caseTitle, caseSummaries.caseSynopsis, RESULTS.resultText
FROM JNCT_RESULT_CASESUMMARY
JOIN caseSummaries ON JNCT_RESULT_CASESUMMARY.caseSummary_FK = caseSummaries.caseID
JOIN RESULTS ON JNCT_RESULT_CASESUMMARY.result_FK = RESULTS.result_ID
GROUP BY caseSummaries.caseID;

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which gives me one row and only the first outcome of three. How can I show the others in the same row? Will I have to create temporary tables and how is that done?
Thanks,
C
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Comment
Question by:cokefour
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7 Comments
 
LVL 61

Expert Comment

by:Julian Hansen
ID: 40374632
Try changing JOIN to LEFT JOIN
0
 
LVL 5

Author Comment

by:cokefour
ID: 40375160
Got the same result
0
 
LVL 61

Expert Comment

by:Julian Hansen
ID: 40375435
Then we need to see some table definition (create table statements)
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LVL 5

Author Comment

by:cokefour
ID: 40375814
Assume from the question I have two tables
Case studies with three fields:
ID
Title
Synopsis
and another table containing Outcomes:
Apology
Compensation
Policy change
There is a many to many relationship and my sql needs to show the outcomes for each case study like this
Case 1 | Title | Synopsis | Apology|Compensation|Policy change
Case 2 |Title | Synopsis |  Apology|NULL|Policy change

assuming the Case 2 only has 2 outcomes.
At the moment without the GROUP BY or  SELECT DISTINCT  I get

Case 1 | Title | Synopsis | Apology
Case 1 | Title | Synopsis |Compensation
Case 1 | Title | Synopsis |Policy change
Case 2 | Title | Synopsis | Apology
Case 2 | Title | Synopsis |Policy change
0
 
LVL 61

Expert Comment

by:Julian Hansen
ID: 40375949
Ok but still need to see table definitions for the three tables

Case Studies (caseSummaries)
Outcomes (Results)
The table that joins them (JNCT_RESULT_CASESUMMARY)
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LVL 5

Accepted Solution

by:
cokefour earned 0 total points
ID: 40382327
Thanks, I got the answer on stackoverflow
SELECT   caseSummaries.caseTitle, 
         caseSummaries.caseSynopsis, 
         GROUP_CONCAT(RESULTS.resultText)
FROM     JNCT_RESULT_CASESUMMARY
JOIN     caseSummaries ON JNCT_RESULT_CASESUMMARY.caseSummary_FK = caseSummaries.caseID
JOIN     RESULTS ON JNCT_RESULT_CASESUMMARY.result_FK = RESULTS.result_ID
GROUP BY caseSummaries.caseTitle, caseSummaries.caseSynopsis;

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Author Closing Comment

by:cokefour
ID: 40391580
I was able to get the answer elsewhere
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