Boolean Variables

If a boolean variable is not initialized it isn’t true or false. Use NVL to have it take the appropriate course.

Declare
 Bool_Var Boolean ;
Begin
 If Not Nvl(Bool_Var,False)
     Then Dbms_Output.Put_Line('False or Not Initialized');
     Else Dbms_Output.Put_Line('True');
 End If;
End;
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