Textbook Notes (369,036)
Canada (162,360)
York University (12,903)
ITEC 1010 (49)
Chapter 3

chapter 3-database notes.pdf

2 Pages
Unlock Document

Information Technology
ITEC 1010
Paul Kashiyama

Chapter 3 database • users never get direct access to database the hierarchy of data • bit: circuit that is either on or off • byte: typically made up of eight bits • character: basic building block of information • field: name, number, or combination of characters that describes an aspect of a business object or activity • record: collection of related data fields • file: collection of related records • database: collection of integrated and related files data entities, attributes, and keys • entity: a general class of people, places, or things (objects) for which data is collected, stored, and maintained • attribute: a characteristic of an entity • key:A field or set of fields in a record that identifies the record • primary key:Afield or set of fields that uniquely identifies the record. The relational database model • manipulating data ◦ selecting: Manipulating data to eliminate rows according to certain criteria. ◦ Projecting: Manipulating data to eliminate columns in a table. ◦ Joining: Manipulating data to combine two or more tables. ◦ Linking: Data manipulation that combines two or more tables using common data attributes to form a new table with only the unique data attributes. Data modeling and database characteristics • when building a database, an organization muse consider ◦ content: what data should be collected and at what cost ◦ access:What data should be provided to which users and when? ◦ Logical structure. How should data be arranged so that it makes sense to a given user? ◦ Physical organization. Where should data be physically located? data center • climate-controlled building or set of buildings that: houses database servers and the systems that deliver mission-critical information and services • traditional data centers:An approach to data management whereby each distinct operational system used data files dedicated to that system. data modeling • logical design: abstract model of how data should be structured and arranged to meet an
More Less

Related notes for ITEC 1010

Log In


Join OneClass

Access over 10 million pages of study
documents for 1.3 million courses.

Sign up

Join to view


By registering, I agree to the Terms and Privacy Policies
Already have an account?
Just a few more details

So we can recommend you notes for your school.

Reset Password

Please enter below the email address you registered with and we will send you a link to reset your password.

Add your courses

Get notes from the top students in your class.