Database Fundamentals

1
Database Fundamentals
2
What is a Database?

• A collection of fields and records (tables) that
  are organized for a particular purpose
• In Access the database encompasses more than just
  data tables. It also includes other parts of the
  whole system
• queries
• forms
• data access pages
• reports
• macros
• modules

3
What is a RDBMS?

• Relational Database Management System
• Each record in the database contains information
  related to a single subject and only that subject
• Two classes of information can be manipulated as
  a single entity based on related data values
• The system manages all data in Tables
• The user can query the database
• The user can join information on related values

4
Relational Database Terminology

• Relation
• Stored as a Table
• Attribute
• Stored as a Column or Field
• Relationship
• Cardinality
• One-to-one, one-to-many, many-to-many
• Join
• Linking tables or queries

5
Database Capabilities

• Data Definition
• Data Manipulation
• Data Control

6
Data Definition and Storage

• Define create table structure
• What data
• Type of data
• Data format
• Data validation
• Data relationship

7
Data Manipulation CRUD

• Create add/insert a new record
• Read query data
• extract, sort, filter, join,
• summarize data
• Update change data in a record
• Delete remove a record

8
Data Control

• Security of data
• Who is allowed to read, update, insert
• Sharing by multiple users
• Updating by multiple users
• Transaction handling

9
Reasons to Use a Database

• Too many separate files or too much data in
  individual files
• Multiple uses for the data
• Sharing data is required
• Control of data is required
• Database handles the one-to-many relationships
  better than flat files