Try OpenEdge Now
skip to main content
Database Essentials
Introduction to Databases : Key points to remember

Key points to remember

The following are some key points to remember:
*A database is an electronic filing system for organizing and storing data that relates to a broad subject area, such as sales and inventory.
*A database is made up of tables. A table is a collection of rows about a specific subject, such as customers.
*A row is a collection of pieces of information about one thing, such as a specific customer.
*A column is a specific item of information, such as a customer name.
*An index is a set of pointers to rows that you use as the basis for searching, sorting, or otherwise processing rows, such as a customer number.
*A primary key is a column (or group of columns) whose value uniquely identifies each row in a table. Because the key value is always unique, you can use it to detect and prevent duplicate rows. It cannot contain null data.
*An index in a database operates like the index tab on a file folder, making it easier to find information.
*A foreign key is a column (or group of columns) in one table whose values are required to match the value of a primary key in another table.