Answer
See the explanation
Work Step by Step
To retrieve the Name and JobTitle of each current employee from the relational database described in Figure 9.5, you can use the following SQL query:
```sql
SELECT Employee.Name, Employee.JobTitle
FROM Employee
JOIN EmploymentHistory ON Employee.EmployeeID = EmploymentHistory.EmployeeID
WHERE EmploymentHistory.EndDate IS NULL;
```
Explanation:
1. **SELECT Employee.Name, Employee.JobTitle**: This selects the Name and JobTitle columns from the Employee table.
2. **FROM Employee**: Specifies the table from which to retrieve the data.
3. **JOIN EmploymentHistory ON Employee.EmployeeID = EmploymentHistory.EmployeeID**: Joins the Employee table with the EmploymentHistory table based on the common EmployeeID column.
4. **WHERE EmploymentHistory.EndDate IS NULL**: Filters the results to include only current employees by checking if the EndDate in the EmploymentHistory table is NULL, indicating that the employee is currently employed.
