Short note on Relational Database.

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 Relational Database

A relational database is a database that stores data in tables that consist of rows and columns. Each row has a primary key and each column has a unique name. A file processing environment uses the terms file, record, and field to represent data. A relational database uses terms different from a file processing system. A developer of a relational database refers to a file as a relation, a record as a tuple, and a field as an attribute. A user of a relational database, by contrast, refers to a file as a table, a record as a row, and a field as a column.

In addition to storing data, a relational database also stores data relationships. A relationship is a link within the data. In a relational database, you can set up a relationship between tables at any time. The tables must have a common column (field). In a relational database, the only data redundancy (duplication) exists in the common columns (fields). The database uses these common columns for relationships. Many organizations use relational databases for payroll, accounts receivable, accounts payable, general ledger, inventory, order entry, invoicing, and other business-related functions.



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