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mysql - How to fix this SQL statement?


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SELECT c.cost_center_name as cost_center_name, 
       COUNT(e.employee) as number_of_employees, 
       SUM(e.w2_wages) as total_wages, 
       c.qualified_percent, 
       c.qualified_percent*SUM(e.w2_wages)*.01 as qualified_wages
FROM cost_center as c
CROSS JOIN employees as e
LEFT OUTER JOIN employees e2 ON e.department = c.cost_center_name
GROUP BY cost_center_name

What is the problem in initial query? The precedence.

Comma has lower priority then JOIN. So FROM clause is totally

FROM cost_center as c, (
                        employees as e
LEFT OUTER JOIN employees e2 ON e.department=cost_center_name
                        )

And when 2 employees copies are joined cost_center_name column which is posessed in cost_center table is not visible.


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