Slide 16.1: A DBMS classification matrix

A DBMS Classification Matrix

	Simple Data	Complex Data
Query	2. Relational DBMS	4. Object-Relational DBMS
No Query	1. File System	3. Persistent Language

If you do not need the service, then there is no need to pay for it in terms of lower performance.

Quadrant 1: Simple Data without Queries
File system is a system for organizing directories and files.
^†A file system has higher performance than more sophisticated systems.

Quadrant 2: Simple Data with Queries

CREATE TABLE  emp (
  name       VARCHAR(30),
  startdate  DATE,
  salary     FLOAT,
  dept       VARCHAR(20) );

CREATE TABLE  dept (
  dname   VARCHAR(20),
  budget  FLOAT,
  floor   INTEGER );

The data is simple because all data are the standard data types of SQL-92.

Find the names of employees with an employment start date after 1980 and who earn more than $40,000.
SELECT name FROM emp WHERE startdate > '1980-12-31' AND salary > 40000;

Find the names of employees who work on the first floor.

SELECT  name  FROM  emp  WHERE  dept  IN (
  SELECT  dname  FROM  dept  WHERE  floor = 1 );

Find the average salary of employees in the marketing department.
SELECT avg( salary ) FROM emp WHERE dept = 'marketing';

Review: A DBMS Classification Matrix

Which system is with complex data and no queries?

Result: