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Lesson 5 How data is stored
Objective Describe how an Access database stores data in a table.

How Data is stored in Access Database

Storing data in Access

In an Access database raw data is stored in tables. Tables are the most basic of the Access database objects, every Access database must have at least one, otherwise you would have no data to work with. Tables are structured with rows and columns; in “database-speak” the rows are called records and the columns are called fields. Here is an example:

Data stored in a table

A field is a category of information. The table shown above has separate fields for first name, last name, address, city, state, and zip code information. Each record is a collection of fields, that is, one piece of data for each field. A record holds related data for one entity. In the table shown, each record holds the contact information for one person.
Unlike a spreadsheet, the rows and columns in a database table cannot be reversed, columns are always fields, which contain a category of data, and rows are always records, which contain a number of pieces of related data.
Breaking Data into Fields It is important to break your data into small, but meaningful, pieces.
Learn what the other Access database objects--queries, forms, and reports are for.

Access Database Analogy

An Access database is nothing more than an automated version of the filing and retrieval functions of a paper filing system. Access databases store information in a carefully defined structure. Access tables store a variety of different kinds of data, from
  1. simple lines of text (such as name and address) to
  2. complex data (such as pictures, sounds, or video images).
Storing data in a precise format enables a database management system (DBMS) like Access to turn data into useful information.
Tables serve as the primary data repository in an Access database. Queries, forms, and reports provide access to the data, enabling a user to add or extract data and presenting the data in useful ways. Most developers add macros or Visual Basic for Applications (VBA) code to forms and reports to make their Access applications easier to use.

Access RDBMS

A relational database management system (RDBMS), such as Access, stores data in related tables. For example, a table containing employee data (names and addresses) may be related to a table containing payroll information (pay date, pay amount, and check number).
Queries allow the user to ask complex questions such as: "What is the sum of all paychecks issued to Byron Janis in 2012?" from these related tables, with the answers displayed as onscreen forms and printed reports. One of the fundamental differences between a relational database and a manual filing system is that, in a relational database system, data for a single person or item may be stored in separate tables. For example, in a patient management system, the patient's name, address, and other contact information is likely to be stored in a different table from the table holding patient treatments. In fact, the treatment table holds all treatment information for all patients, and a patient identifier (usually a number) is used to look up an individual patient’s treatments in the treatment table.

In Access, a database is the overall container for the data and associated objects. It’s more than the collection of tables, however—a database includes many types of objects, including queries, forms, reports, macros, and code modules.
As you open an Access database, the objects (tables, queries, and so on) in the database are presented for you to work with. You may open several copies of Access at the same time and simultaneously work with more than one database, if needed.