A database or database management system that stores
information in tables—rows and columns of data—and conducts searches by using
data in specified columns of one table to find additional data in another table.
In a relational database, the rows of a table represent records (collections of
information about separate items) and the columns represent fields (particular
attributes of a record). In conducting searches, a relational database matches
information from a field in one table with information in a corresponding field
of another table to produce a third table that combines requested data from both
tables.
For example, if one table contains the fields EMPLOYEE-ID, LAST-NAME,
FIRST-NAME, and HIRE-DATE, and another contains the fields DEPT, EMPLOYEE-ID,
and SALARY, a relational database can match the EMPLOYEE-ID fields in the two
tables to find such information as the names of all employees earning a certain
salary or the departments of all employees hired after a certain date. In other
words, a relational database uses matching values in two tables to relate
information in one to information in the other. Microcomputer database products
typically are relational databases. Compare flat-file
database, inverted-list database.
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