Database- Logical Database Design
Database- Logical Database Design
11. A relation has which of the following properties?
- Each row is not unique.
- Attributes can have the same name within a given table.
- Each relation has a unique name.
- The order of the columns is significant.
12. When mapping a ternary relationship with an associative entity into a relation which of the following is true?
- One relation is created.
- Two relations are created.
- Three relations are created.
- Four relations are created.
13. When mapping a regular entity into a relation which of the following is true?
- One relation is created.
- Two relations are created.
- Three relations are created.
- Four relations are created.
14. When mapping a supertype/subtype relationship which of the following is true?
- The supertype primary key is assigned to each subtype.
- The subtype primary key is assigned to each supertype.
- There is no link between the supertype/subtype entities.
- There is no primary key/foreign key relationship between a supertype/subtype.
15. Relations are:
- two-dimensional tables.
- three-dimensional tables.
- four-dimensional tables.
- five-dimensional tables.