quiz 3

1. A _______________ constraint ensures that every value in a column is unique within a table.

Answer explanation

2. A _______________ constraint is used to establish relationships between tables based on commoncolumns

3. The _______________ constraint enforces that a column cannot have NULL values.

4. The purpose of the _______________ constraint is to prevent duplicate values in a column.

5. The SQL command used to add a new constraint to an existing table is _______________.

6. To retrieve all rows from a table, you can use:

   SELECT * FROM _______________;

7. To sort query results by one or more columns, you can use the _______________ clause.

8. Aggregation functions like _______________, _______________, and _______________ are used to perform calculations on groups of data.

9. The _______________ clause is used to specify conditions for filtering rows.

10. To calculate the average salary for each department, you can use the _______________ function in combination with the _______________ clause.