In this lesson you created the database that you designed in Lesson One. Remember, always design your database on paper before building it. This will save you hours of time and frustration. You did the following:
•Named the SkyWrite database
• Defined the Employee, Customer, and Flights tables
• Defined the columns for each table and selected data types for each column
• Designated EmployeeID, CustomerID, and FlightID as auto-numbered columns
• Designated EmployeeID, CustomerID, and FlightID as primary keys to ensure data integrity
• Designated EmployeeID and CustomerID as foreign keys to ensure data integrity
• Designated FlightDate as an indexed column for faster processing
• Looked at the structure of the SkyWrite database
• Added the computed column TotalCharge to the Flights table
• Created two quick rules
• Listed rules
• Modified the rule and messages
To check your knowledge, try answering the following questions:
| 1. | How do you start the Data Designer? |
| 2. | How many tables can be defined for one database? |
| 3. | How many columns can be defined for one table? |
| 4. | What must you do to designate a column as indexed for faster processing by R:BASE? |
| 5. | What is an example of data that would match the INTEGER data type? |
| 6. | How do you designate a column as an autonumbered column? |
| 7. | What function key displays the tables and columns in the database? |
| 8. | What is the command from the R> Prompt that displays database information? |
| 9. | What is a computed column? |
| 10. | Can you enter or update values in a computed column? (Yes- No) |
| 11. | Why do you define rules for a database? |
