This glossary contains explanations of some of the terms used in this manual.
Cross-references to other entries are given in bold type.
- application, database
- A database application is a computer program to
help users of a specific database. RDMSs provide an
application language so that a programmer can create this program.
- attribute
- A piece of information about an item or entity. For
example, hair colour is an attribute of a person, population is an attribute
of a town.
- column
- A database table will usually consist of many
rows and columns, just like a table in a book. Each column will
store information about an attribute. A table of people may have
columns for height, hair colour, eye colour,
- database
- A structured collection of data.
- database application
- See application, database.
- database management system
- A computer program for storing and
manipulating data.
- DMS
- See database management system.
- entity
- An group of items about which data is stored; for
example `stone' or `site'. Entities are usually represented by a
table or relation with one or more attributes; an entry
in the table, a particular stone, is an instance.
- form
- A form in a computing context is a structured way of displaying
and/or entering data on screen. It is analogous to the more common paper
form.
- instance
- A particular example or entry of an
entity; Welwyn Garden City is an instance of the
entity `towns'.
- normalisation
-
- relation
- A special type of table in which (a) every row is
unique, (b) the columns are in no fixed order and (c) the rows are
in no fixed order. All the tables in a relational
database will be relations.
- relational database
- is a particular way of structuring data
which will consist of multiple relations and is
manipulated using a relational database management system.
- relational database management system
- A computer program for storing
and manipulating data which has been structured to a form a relational
database.
- RDMS
- See relational database management system.
- row
- A database table will usually consist of many rows and
columns, just like a table in a book. Each row will store
information about an entity. A table of people may have a row for
each person.
- table
- A set of data organised in a tabular form with rows and
columns similar to a table in a book. A database usually consists of
several tables. Tables many be linked via a key field.
- tuple
- Another name for a row.
- variable
- A term often loosely used to mean attribute. The
term should be avoided as it has other meanings in a computing context.
Mike Gahan
2000-10-18