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A.Define the column MAINID as NOT UPDATABLEB.Define the……

Which of the following can be used to ensure that once a row has been inserted in table TABLEX, the column MAINID in that row cannot be updated?()

A.Define the column MAINID as NOT UPDATABLE
B.Define the column MAINID as a PRIMARY KEY
C.Define the column MAINID as a FOREIGN KEY
D.Define an UPDATE trigger on table TABLEX

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