Module 7a:Structuring and Storing Data
Relationship between attributes and entities
Each record in an entity occupies one row in its respective table
Reason Database offers increased information security
Various security features of databases ensure that individuals have only certain types of access to certain types of information
Information integrity
a measure of the quality of information
Relational Database Management System
allows users to create, read, update and delete data in a relational database
Data models
are logical data structures that detail the relationships among data elements using graphics or pictures
Integrity constraints
are rules that help insure the quality of information.
Attributes (Columns/Fields)
are the data elements associated with an entity
structured query language (SQL)
asks users to write lines of code to answer questions against a database.
Data Dictionary
compiles all of the metadata about the data elements in the data model.
Database Management System(DBMS)
creates, reads, updates and deletes data in database while controlling access and security.
Physical View of Information
deals with the physical storage of information on a storage device.
Business Rule
defines show a company performs certain aspects of its business and typically results in a yes/no or true/false answer.
Business-Critcal integrity constraints
enforce business rules vital to an organizations success and often require more insight and knowledge than relational integrity constraints.
Logical view of information
focuses on how individual users logically access information to meet their own particular business needs.
query-by-example (QBE) tool
helps users graphically design the answer to a question against a database.
Primary
is a field that uniquely identifies a given record in a table
Foreign Key
is a primary key of one table that appears as an attribute in another table and acts to provide a logical relationship between the two tables.
Record
is the collection of related data elements
Information redundancy
is the duplication of data, or the storage of the same data in multiple places.
Database
maintains information about various types of objects (inventory), event (transactions), people (employees), and places (warehouses).
Metadata
provides details about data
Relational integrity constraints
rules that enforce basic and fundamental information based constraints.
Entity
stores information about a person, place, thing, transaction, or event.
Relational Database Model
stores information in the form of logically related two-dimensional tables.
Data Element (Data Field)
the smallest or basic unit of information
Business Advantages of a Relational Database
1.Increased flexibility 2.Increased Information integrity 3.Increased scalability and information 4.Increased information security 5.Reduced Information redundancy