Important Terms

 

A flat file is a type of database where all information is contained in one file.

A flat file database manager is a software program that looks after a single file.

It is simple, easy to use and cheap.

 

A database management system (DBMS) is a software program that looks after more than one file. It allows a user to systematically organise and manipulate data in more than one file.

A DBMS has four features

1.                  A query language which allows you to view, combine, choose and limit display of data.

2.                  A report generator.

3.                  A data definition language.

4.                  A data manipulation language.

 

 

 

The three types of databases are

1.                  HIERACHICAL DATABASE which has a tree structure

 

 

 

 

 

 

 

 

 

2.                  NETWORK DBMS

 

 

 

 

 

 

 

 

 

 

 

 

 

RELATIONAL DBMS where data elements are put into a table (relational name for file). Tuples (rows in a table) contain Records AND Attributes (columns in a table) contain fields. Each database has a Primary Key which is unique. Keys identify tuples and relate databases.