troubleshooting Question

SQL _ Cartesian Product

Avatar of hdcowboyaz
hdcowboyazFlag for United States of America asked on
MySQL Server
11 Comments1 Solution299 ViewsLast Modified:
I'm getting a Cartesian Product on the query below.
I'm getting 42 records and should be getting 3.
There are 14 extra's for that job... 42/3 = 14.

This is the part of the statement that returns the Cartesian Product.
- LEFT JOIN extra ex ON (ex.JOB_ID = j.JOB_ID)

See attached ERD

 SELECT
 j.JOBID 'Job',
 j.DSCR 'Job Name',
 ex.ExtraID 'Extra',
 c.CostCode 'Cost Code',
 e.EMPID 'Emp ID',
 l.HOURS 'Hours'
 FROM labor l
 LEFT JOIN emp e ON (e.EMP_ID = l.EMP_ID)
 LEFT JOIN job j ON (j.JOB_ID = l.JOB_ID)
 LEFT JOIN extra ex ON (ex.JOB_ID = j.JOB_ID)
 LEFT JOIN ccode c ON (c.EXTRA_ID = ex.EXTRA_ID)
 WHERE DATE_WORK = '2014-11-3'
 AND l.DELETED = 'N'
 AND j.JOB_ID = 37014;
ERDTheEdgeLaborEntry.jpg
ASKER CERTIFIED SOLUTION
Steve Wales
Senior Database Administrator

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