When designing a database, we must decide
Which of the following is true about the benefits of a database :
1. Data entry, updates and deletions will be efficient.
2. Data retrieval, summarization and reporting will be efficient.
3. Since the database follows a well-formulated model, it behaves unpredictably.
4. Changes to the database schema are easy to make.
A Primary key is:
All columns (or combination of columns) in a table with unique values are referred to as:
A foreign key is:
Which of the following is true :A relation is a special type of table that has the following attributes:
1. They describe one entity.
2. They have no duplicate rows; hence there is always a primary key.
3. The columns are unordered.
4. The rows are unordered.
Every higher normal form is a superset of all lower forms.
A row may not be added to a table with a foreign key unless the referenced value exists in the referenced table.
There are three options available when a referenced primary key value changes or a row is deleted, they are:
The relational database model was created by ________ in ______ and is founded on set theory and logic