Set - 10

Question 76 :

What is the difference between foreign key and reference key ?

Answer :

Foreign key is the key i.e. attribute which refers to another table primary key. Reference key is the primary key of table referred by another table.


Question 77 :

Can dual table be deleted, dropped or altered or updated or inserted ?

Answer :

Yes


Question 78 :

If content of dual is updated to some value computation takes place or not ?

Answer :

Yes


Question 79 :

If any other table same as dual is created would it act similar to dual?

Answer :

Yes


Question 80 :

For which relational operators in where clause, index is not used ?

Answer :

<> , like '% ...' is NOT functions, field +constant, field || ''