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Composite Key

Consider a relation 

project(E_id,P_id,hrs)

E_id+P_id = Candidate key or Composite Key??

 

2Comments
Parimal Andhalkar @parimal_andhalkar
19 Dec 2015 11:27 pm

Candidate key = Minimal superkeys . Any one candidate key can be used as primary key.

candidate key and primary key can have single or more attributes.

Composite key is combination of more than one column that can identify row uniquely.

composite key can be combination of primary key and candidate key.

so finally, composite key always contain more than one column (ie 2 or more)

E_id+P_id = composite key 

 

Chirantan Das @chirantantab
20 Dec 2015 12:06 am

Thanks for ur well explanation