Question

Set the composite primary key for the Course table. To do this you first select one field, and then while holding the Control key down select the other field. With both fields selected, click the Primary Key button: 1\. Select the deptCode (click to the left of the deptCode field). 2\. To select the next field to be part of the PK: while holding the Control key down, click the courseNo field (and now release the Control key). 3. Next, click the Primary Key icon. You will now see the key image beside both fields as in: If MS Access rejects your primary key then you must examine the values you previously entered for deptCode and courseNo - there must be some duplicated value. If this happens open the table in Datasheet View and examine the rows to find duplicate values of the combination \{deptCode, courseNo\}. Once MS Access has accepted your primary key you should open the table in datasheet view and experiment: How does MS Access respond if you try to create a new row with an existing primary key value?

Short answer

To set a composite primary key in MS Access, select the first field (deptCode) and then while holding Control, select the second field (courseNo). Click the Primary Key icon to establish these two as your composite primary key. In case of rejection, check for duplicated values in these fields and eliminate them before trying again.

Step-by-step solution

Select the first field for the primary key

In your MS Access, locate the Course table and select the first field for your primary key by clicking to the left of the 'deptCode' field.

Choose the second field of the primary key

Continue by holding down the Control key and then clicking the 'courseNo' field. With that done, you can release the Control key. You have now selected the two fields that will make up your composite primary key.

Create the primary key

Now, find and click the 'Primary Key' icon. If done correctly, you should see a key image beside both 'deptCode' and 'courseNo' fields.

Troubleshoot potential issues

In the event that MS Access rejects your primary key, this is often due to duplicate values in your 'deptCode' and 'courseNo' fields. To fix this, open the table in Datasheet View and look for these duplicates. Once found, remove or change the duplicated values.

Test the primary key and observe results

With your composite primary key accepted and set, try creating a new row with an existing primary key value. Observe how MS Access reacts to this. It should prevent you from creating a new row with a duplicate primary key, as these need to be unique in each database table.

Key concepts

Microsoft Access

Microsoft Access is a powerful database management tool used to organize and manage large amounts of information. With user-friendly features, it allows individuals to create and manipulate databases without needing extensive knowledge in programming. Access provides a variety of tools used for building and customizing databases, including table creation, query processing, and form design.

One of the distinctive features of Access is its ability to handle relational data. Users can define the relationships between tables, providing a way to connect and retrieve related data in a context that supports both simplicity and complexity. It's this relational aspect of Access that empowers users to create databases that reflect real-world data structures and relationships.

Database Design

The principles of database design are crucial for creating efficient and reliable databases. Good database design prevents data redundancy, ensures data integrity, and supports easy maintenance. Database design typically starts with defining the tables and the relationships between them.

The design process includes determining which information should be stored and how it should be divided into tables. Each piece of information, or field, within a table should serve a single purpose and be well-defined. Tables are then connected through relationships, often using a primary key, which is a unique identifier for each record. In a well-designed database, every piece of data is stored once and referenced elsewhere whenever needed, keeping your data coherent and consistent.

Primary Key Validation

Primary key validation is a fundamental aspect of ensuring database integrity. A primary key is a unique identifier for each record in a database table and it must not be duplicated. When defining a primary key, one must ensure that the field or combination of fields chosen as the primary key contains only unique values.

In Microsoft Access, when you set a primary key, the program automatically enforces primary key validation. This means if you attempt to enter a duplicate primary key value, Access will generate an error message and prevent the duplicate entry. Validating primary keys maintains data integrity by assuring that each record can be uniquely identified which is critical for tasks such as updating or deleting specific records.

Datasheet View

The Datasheet View in Microsoft Access offers a spreadsheet-like interface for viewing and editing table data. This view is intuitive for users since it resembles Excel, making it easy to navigate and manipulate data fields. You can sort and filter data, search for records, and directly enter and update data in this view.

Using Datasheet View is particularly helpful when you need to troubleshoot issues such as finding and correcting duplicate entries when setting a composite primary key. It provides a clear and comprehensive view of all records which aids in identifying and fixing any data entry problems swiftly. Access's Datasheet View is therefore an essential feature for regular data maintenance and review activities.