An example might be Product ID or Order ID. The primary key is a column that is used to uniquely identify each row. For example, an Employees table might include fields such as Last Name and Hire Date.Ĭhoose each table’s primary key. Each item becomes a field, and is displayed as a column in the table. Each subject then becomes a table.ĭecide what information you want to store in each table. Gather all of the types of information you might want to record in the database, such as product name and order number.ĭivide your information items into major entities or subjects, such as Products or Orders. This helps prepare you for the remaining steps.įind and organize the information required The design process consists of the following steps: Helps support and ensure the accuracy and integrity of your information.Īccommodates your data processing and reporting needs. Provides Access with the information it requires to join the information in the tables together as needed. As a result, any decisions you make that are based on those reports will then be misinformed.Ī good database design is, therefore, one that:ĭivides your information into subject-based tables to reduce redundant data. If your database contains incorrect information, any reports that pull information from the database will also contain incorrect information. The second principle is that the correctness and completeness of information is important. The first principle is that duplicate information (also called redundant data) is bad, because it wastes space and increases the likelihood of errors and inconsistencies. Top of Page What is good database design?Ĭertain principles guide the database design process. Each column or field holds some type of information about that product, such as its name or price. In the Products table, for instance, each row or record would hold information about one product. A field is a single item of information - an item type that appears in every record. A record is a meaningful and consistent way to combine information about something. For example, you might have a table that stores information about products, another table that stores information about orders, and another table with information about customers.Įach row is more correctly called a record, and each column, a field. For most databases you will need more than one. In a simple database, you might have only one table. In this articleįinding and organizing the required informationĪccess organizes your information into tables: lists of rows and columns reminiscent of an accountant’s pad or a spreadsheet. You should read this article before you create your first desktop database. You will learn how to decide what information you need, how to divide that information into the appropriate tables and columns, and how those tables relate to each other. This article provides guidelines for planning a desktop database. In the end, you are much more likely to end up with a database that meets your needs and can easily accommodate change. Because a correct design is essential to achieving your goals in working with a database, investing the time required to learn the principles of good design makes sense. A properly designed database provides you with access to up-to-date, accurate information.
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