Workshop_6

Notice the word ascending appears in the sort row of

Info iconThis preview shows page 1. Sign up to view the full content.

View Full Document Right Arrow Icon
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: bottom determine how to act on related fields and records when a field is modified. Note: In NeoOffice this is automatically done for you already. 8. Click on the Create button to create the relationship. The Relationships window will now disappear and a line will be drawn between the SSN fields in the two tables. Notice that a “1” appears next to the Student Info table representing a one to one relationship and an “∞”appears next to the Course Sign ­ups table to signify a one ­to ­many relationship. This means that one record from the Student Info is related to potentially many records in the Course Sign ­ups. 9. Relate the Course Offerings and Course Sign ­ups tables by the CRN field following the example above. Below shows how the relationships should look if you followed the steps correctly. Under Windows: Under OS ­X: 10. Exit out of the Relationships window by selecting FILE → CLOSE. If the computer asks if you want to save the layout changes, answer Yes. 14 Workshop 6: MS Office Access and NeoOffice 11. To delete or modify a relationship between two tables, you must be in the Relationships window. Click on the line drawn between the tables and press the delete key on the keyboard to delete. Double ­click on the middle of the line to open the Edit Relationships window. Relating Tables In this section you will learn what a query is, and you progress from creating simple one ­table queries to more complex multi ­table queries. What is a query? A query is like a question that you ask or a task you give to the database. Queries are used anytime there is a need to process the basic raw data into information that addresses a practical question. They are used to view, analyze, and change data, supply information to forms and reports, and for database ­driven web pages. Queries may be based on one or more tables, and may involve calculations, or procedures such as sorting, based on subsets of fields from those tables. For example, you might want to compare the average of bookstore charges incurred by juniors to the average for seniors. This requires that you find the student ID for all juniors and seniors, total the bookstore charges for those two groups, divide each one by the number of different IDs in each group, and display the information in a meaningful way. In short, you need a query. Types of Queries Although queries are very flexible and general, they are classified into several types depending on the main purpose of the quer...
View Full Document

This note was uploaded on 06/03/2012 for the course PLS 21 taught by Professor Lieth during the Summer '08 term at UC Davis.

Ask a homework question - tutors are online