1-*
1 Means each Detail row must corresponds to one master row
* Means each master row can correspond to any number of detail row
0..1-*
“0..1” means each detail row can correspond to 0 or 1 master row.
1-1
This is pure one to one cardinality
Most used relationships for better normalized schema are one to one , one to many , many to one and many to many.
Remember that many to many relationship has 3 table , one source , one destination and one intersection table that map between two.
HR Schema has Employee , Job , JobHistory
TableEmployee – EmployeeId
JobHistory – EmployeeId , JobId
TableJob – Jobid
GREAT! SIMPLE
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