Because for each (one) customer, there is only one possible piece of data to record in the column, you say that the relationship between the data and the entity is “1 to 1.” If this is the type of database that you are trying to create, simple Microsoft Excel tables will work well. So, what is the meaning of this “1 to 1” relationship between the entity (the customer) and the data you are recording (“FirstName,” “LastName,” etc.)? What this means is that for each entity, or subject, (in this case- the customer), you are only recording information about that entity for which there would only be one “answer.” For example, each customer would only have one “first name” and one “last name.” They would work for only one “company.” So the term “1 to 1” refers to the relationship between the subject of the table (customers) and the data being collected about the entities. The reason that this type of data structure works well in the example given is because for each entity (the customer), you are only recording information that has a “1 to 1” relationship to the entity. What you are doing when using this type of database is recording a single piece of information, like the “FirstName,” “LastName,” or “Address,” about a single entity- in this example, a customer. Assume it looks like the following example.įor many types of databases, the structure shown on the previous page would work well. You can then list each customer’s information in the rows underneath the columns, creating a basic table.
Perhaps you could create a table in an application like Microsoft Excel where you can create columns for each piece of information that you wish to record. You may want to record customer information like the “first name,” the “last name,” the “company name,” and other relevant pieces of information. You would begin by listing the different attributes of the customer that you wish to record. Information is frequently stored in large ‘flat-files.’ For example, assume that you want to create a database file that stores your company’s customer information.
However, it may be easier to understand the relational model of data storage by contrasting it with another method of storage that you may be more familiar with: the ‘flat-file’ method. So what does the term relational mean, and how is this important? The term relational describes the method used for storing data within the database tables. This is the main reason that you use databases: to enter, store, and retrieve data.Īccess is a relational database application. Once this system is in place, you can automate it by using macros and modules to simplify and streamline the processes involved in entering, storing and retrieving data. The queries often form the basis for reports, which will then allow you to view the information you requested. You can the use queries to pull specific information from the tables in the database. The data is then stored into these tables, which are related to each other as necessary. In general, you use forms to enter information into tables. Once that is done, the new blank database will appear in the main Access interface.Ī database should be simple, logical, and straightforward in its design. Then click the “Create” button to create the new database file. When you are ready, click the “OK” button to close the dialog box.
Use this dialog box to give the new database file a name and also select where you want to save the file. If you want to change the default folder where the database file will be stored, you can click the small folder button at the right end of the “File Name:” text box in order to launch the “File New Database” dialog box. In the “Blank Database” pane that appears at the right side of the screen, you can enter a name for the database into the “File Name:” text box. In Access 2007, you can create a new blank database by simply clicking the “Blank Database” button In the “New Blank Database” section of the “Getting Started with Microsoft Access” welcome screen. Then select the “Blank database” choice in the “Available Templates” section. In Access 2010, you can create a new database by clicking the “File” tab in the Ribbon. A new database is a container that will hold all of the tables, form, reports, queries, macros, and modules that you create.
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