Fundamentals ofDatabase Design John Villamil-Casanova Executive Vice President & CIO The Aspira Association 202.835.3600 ext. 123 firstname.lastname@example.org
AgendaIntroduction and participants needsWe will review “what is a database;”Understand the difference between dataand information;What is the purpose of a databasesystem;How to select a database system;Database definitions and fundamentalbuilding blocks;
Agenda (2)Database development: the first steps;Quality control issues;Data entry considerations;
What is a databaseA 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 VolunteersTo keep a record of activitiesand interventions;Keep sales records;Develop reports;Perform researchLongitudinal tracking
What is the ultimate purpose of a database management system? Is to transform Data Information Knowledge Action
More about database definitionWhat 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 examplesOutlook contactsAspira Association MISKidTraxGIS-GPS systems
Types of DatabasesNon-relational databasesNon-relational databases place information in field categories that we create sothat 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 andcannot be extracted and applied to a number of other software programs, orother database files within a school or administrative system. The datacan only be "copied and pasted.“ Example: a spread sheetRelational databasesIn relational databases, fields can be used in a number of ways (andcan be of variable length), provided that they are linked in tables. It isdeveloped based on a database model that provides for logicalconnections among files (known as tables) by including identifyingdata from one table in another table
Selecting a Database Management SystemDatabase 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 AnalysisThe 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 students information, a recipe, a test question A layout: a design for a database that contains field names and possibly graphics.Database glossary
Fundamental building blocksTables comprise the fundamental building blocks of any database. If youre familiar withspreadsheets, youll find database tables extremely similar. Take a look at this example ofa table sample database:The table above contains the employee information for our organization -- characteristicslike name, date of birth and title. Examine the construction of the table and youll find thateach column of the table corresponds to a specific employee characteristic (or attribute indatabase terms). Each row corresponds to one particular employee and contains his or herinformation. Thats all there is to it! If it helps, think of each one of these tables as aspreadsheet-style listing of information.
Where do we start?Let’s explore your “papersystem” Client intake forms Job application form Funders reportsDatabase modeling: Define required fields from “forms” or required reports Avoid repetition Keep it simple Identify a unique identifier or primary key
Some Quality Control ConsiderationsRemember “garbage in –garbage out”. Some examplesand how to prevent this.Quality managementencompasses three distinctprocesses: quality planning,quality control, and qualityimprovementQuality Planning in relation todatabase systems design: Who will perform data entry? Training? On-line help? How data entry will be performed?
Data entry considerationsDefine “must” enter fields – no record is completeunless: such and such is entered;Make data entry fool proof. Example: Grade level canbe entered as a number (8 or 8th or eight). By using apull-down menu with the correct data format thesemistakes 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)