Q14: TRUE or FALSE:

- A Nave database user, is the user who works on database infrequently (when needed) ( )

- We may not using DBMS when it costs more than the benefits. ( )

- The conceptual data model describes details of how data is stored in the computer. ( )

- Relation Schema R of degree n is denoted by: R(A1, A2, A3) ( )

- A Supper Key is: A key that no two tuples in any valid relation instance r(R) will have the same value for SK. ( )

- If a relation has several candidate keys, we MUST chose the first key to be a primary key. ( )

- In key constraint, a supper key must not have NULL value. ( )

- In Referential Integrity, The primary key attributes PK of each relation schema R in S cannot have null values in any tuple of r(R). ( )

- A referential integrity constraint can be displayed in a relational database schema as a directed arc from R1.FK to R2. ( )

- The value in the Foreign Key column (or columns) FK of the referencing relation R cannot be NULL. ( )