Negated SELECT queryam 17.03.2009 17:42:43 von BobTheBowler
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3 tables are related by one-many links.
Employees ---<- Assets ---<- Maintenance
Employees can be assigned =3D> 0 Assets
Assets can have =3D> 0 occurances of Maintenance.
Assets table contains EmployeeIDs and MaintenanceIDs,
but no Foreign Key contraints.
1) which Employees do not have any Assets =3F
2) which Assets have not had any Maintenance =3F
These have been written successfully with Sub-Queries,
I would like to know how they can be done with only JOINs =3F
(that also means without the EXCEPT statement)
Is that too much of a challenge =3F (MySQL 5.0.67)
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