NURS 736: Technology Solutions for Knowledge Generation in Healthcare Module 2: Database and Database Models

Definitions A Database is a shared collection of logically related data, designed to meet the information needs of multiple users in an organization DataBase Management System (DBMS): software that helps organize data in a way that allows fast and easy access to the data

Databases Advantages Disadvantages Reduced redundancy one place; single entry Integrated data retrieved from anywhere in database available for queries/reports Integrity accurate and up to date Disadvantages Can be expensive to set up Direct access to data may be limited Data excess

Database Design From smallest to largest unit: Character Field Record File Database

Database Models Types of DB Models: Flat Hierarchical Network Object oriented Relational

Database Models: Flat Binary file; contains one record per line Fields separated by delimiters, e.g. commas, or may have a fixed length No relationship between the records Example: Creating a name and address list on paper, in a word processing program or a spreadsheet. This would be called a “flat file”

Database Models: Hierarchical Example: magnetic tape, Step-like with no shortcuts Rigid, inefficient Forced series of steps to reach data you need

Database Models: Network Similar to hierarchical Redundant copies of same dataset on several networked computers Allows shortcuts

Database Models: Object Oriented inherits SUV Sports Car Automobile aggregation Super Class Passenger transport Passengers: 2 Passengers: 7 plus payload Payload Heavy duty: 800 lb capacity Object oriented model – most advanced for storing data Data attributes and functions contained within database “objects” which are reusable

Database Models: Relational Data is organized into two dimensional table Can retrieve data across all files directly without going through pathways Can extract key information

Database Models: Relational Patient Order Type Results Date Order # RBC Result # Last Name SSN Zip Code Requests WBC Figure 1: Relational Database Relational DB. Data using tables and relationships. Nearly all current databases have adopted this model as their standard. This type of table depends on TABLES and RELATIONSHIPS between those tables.

Relational Terms Column=Category The fields in the table (columns) give information about one type of category

Relational Terms Row=result The records in the table (rows) give the information about one specific result

Tables & Relationships Patient has an order Order has a result “relationship” This is an example of tables and relationships for a relational database. Emphasize the tables and the relationships between them. Note that there is a field in each table that links one to another (SSN links to order table & order # links to results table)