Documents
Resources
Learning Center
Upload
Plans & pricing Sign in
Sign Out

database

VIEWS: 25 PAGES: 18

									Fundamentals of
Database Design

    John Villamil-Casanova
 Executive Vice President & CIO
    The Aspira Association
     202.835.3600 ext. 123
      jvillamil@aspira.org
              Agenda
Introduction and participants needs
We will review “what is a database;”
Understand the difference between data
and information;
What is the purpose of a database system;
How to select a database system;
Database definitions and fundamental
building blocks;
            Agenda (2)
Database development: the first steps;
Quality control issues;
Data entry considerations;
           What is a database
A database is any organized collection of
  data. Some examples of databases you
  may encounter in your daily life are:
     a telephone book
     T.V. Guide
     airline reservation system
     motor vehicle registration records
     papers in your filing cabinet
     files on your computer hard drive.
        Data vs. information:
       What is the difference?
What is data?                  What is information?
   Data can be defined in        Information is data that
    many ways. Information         have been organized and
    science defines data as        communicated in a
    unprocessed information.       coherent and meaningful
                                   manner.
                                  Data is converted into
                                   information, and
                                   information is converted
                                   into knowledge.
                                  Knowledge; information
                                   evaluated and organized
                                   so that it can be used
                                   purposefully.
Why do we need a database?
Keep records of our:
  Clients
  Staff
  Volunteers
To keep a record of activities
and interventions;
Keep sales records;
Develop reports;
Perform research
Longitudinal tracking
What is the ultimate purpose of
  a database management
           system?
         Is to transform

 Data   Information   Knowledge   Action
 More about database definition
What is a database?
Quite simply, it’s an organized collection of data.
 A database management system (DBMS) such
 as Access, FileMaker, Lotus Notes, Oracle or
 SQL Server which provides you with the
 software tools you need to organize that data in
 a flexible manner. It includes tools to add,
 modify or delete data from the database, ask
 questions (or queries) about the data stored in
 the database and produce reports summarizing
 selected contents.
Let’s explore some examples
Outlook contacts
Aspira Association MIS
KidTrax
GIS-GPS systems
            Types of Databases
Non-relational databases
Non-relational databases place information in field categories that we create so
that information is available for sorting and disseminating the way we need it.
The data in a non-relational database, however, is limited to that program and
cannot be extracted and applied to a number of other software programs, or
other database files within a school or administrative system. The data
can only be "copied and pasted.“ Example: a spread sheet


Relational databases
In relational databases, fields can be used in a number of ways (and
can be of variable length), provided that they are linked in tables. It is
developed based on a database model that provides for logical
connections among files (known as tables) by including identifying
data from one table in another table
          Selecting a Database
          Management System
Database management systems (or DBMSs) can be divided into
  two categories -- desktop databases and server databases.
  Generally speaking, desktop databases are oriented toward
  single-user applications and reside on standard personal
  computers (hence the term desktop).
  Server databases contain mechanisms to ensure the reliability
  and consistency of data and are geared toward multi-user
  applications.
   Selecting a database system:
           Need Analysis
The needs analysis process will be specific to your organization but, at
  a minimum, should answer the following questions:
  How many records we will warehouse and for how long?
  Who will be using the database and what tasks will they perform?
  How often will the data be modified? Who will make these
  modifications?
  Who will be providing IT support for the database?
  What hardware is available? Is there a budget for purchasing
  additional hardware?
  Who will be responsible for maintaining the data?
  Will data access be offered over the Internet? If so, what level of
  access should be supported?
               Some Definitions
 A File: A group or collection of similar records, like INST6031 Fall
 Student File, American History 1850-1866 file, Basic Food Group
 Nutrition File
 A record book: a "rolodex" of data records, like address lists,
 inventory lists, classes or thematic units, or groupings of other
 unique records that are combined into one list (found in AppleWorks,
 FileMaker Pro software).
 A field: one category of information, i.e., Name, Address, Semester
 Grade, Academic topic
 A record: one piece of data, i.e., one student's information, a recipe,
 a test question
 A layout: a design for a database that contains field names and
 possibly graphics.

Database glossary
Fundamental building blocks
Tables comprise the fundamental building blocks of any database. If you're familiar with
spreadsheets, you'll find database tables extremely similar. Take a look at this example of a
table sample database:




The table above contains the employee information for our organization -- characteristics
like name, date of birth and title. Examine the construction of the table and you'll find that
each column of the table corresponds to a specific employee characteristic (or attribute in
database terms). Each row corresponds to one particular employee and contains his or her
information. That's all there is to it! If it helps, think of each one of these tables as a
spreadsheet-style listing of information.
            Where do we start?
Let’s explore your “paper
system”
   Client intake forms
   Job application form
   Funders reports
Database modeling:
   Define required fields from
    “forms” or required reports
   Avoid repetition
   Keep it simple
   Identify a unique identifier
    or primary key
         Some Quality Control
           Considerations
Remember “garbage in –
garbage out”. Some examples
and how to prevent this.
Quality management
encompasses three distinct
processes: quality planning,
quality control, and quality
improvement
Quality Planning in relation to
database systems design:
  Who will perform data
   entry?
  Training? On-line help?
  How data entry will be
   performed?
   Data entry considerations
Define “must” enter fields – no record is complete
unless: such and such is entered;
Make data entry fool proof. Example: Grade level can
be entered as a number (8 or 8th or eight). By using a
pull-down menu with the correct data format these
mistakes can be avoided.
Data Entry – additional
   considerations
             Barcode scanners
                 USB or
                 Wireless attached to a
                  Palm or Pocket PC
             Pocket PC
                 WiFi 802.11g,
                  Bluetooth
                 Wireless networks
                  (real-time on demand
                  systems)

								
To top