Class notes
Theory Revision Grade 12
A document providing all the necessary information on theory to do well in the IT paper 2
[Show more]
Connected book
Book Title:
Author(s):
- Edition:
- ISBN:
- Edition:
Seller
Follow
Content preview
TERM2 THEORY REVISIONData Collection
- Refers to the process of gathering and measuring information in a
digital format from various sources for processing, storage, analysis,
and utilization.
RFID
- Radio Frequency Identification
- Data capture technology that was designed to store more data and
work more interactively than conventional barcode systems.
- Uses radio frequencies to identify objects by means of tags attached
to the object
- Examples Pets, eTolls
- Makes data capture efficient
- Tag placed on item, reader reads the tag for info
Parts of RFID
The Tag
- Contains antenna, circuitry and a microchip, sometimes a battery
- Sizes vary
- Size of antenna makes the communication possible at different
distances
The Reader
- Uses antenna, creates electromagnetic field that is used for passive
tags to create electricity for themselves
- Reader reads the radio signals broadcasted by tags and sends info
to software for processing
- Reader can also be any size
Advantages
- Read more than one tag at a time
- Read tags even if they are in boxes
- Interact with data and software stored on tag
- Read tags when they travelling at speed
, - Use tag to collect and broadcast info about the
environment(temperature)
Data Warehousing
- Huge collection of data, often accumulated from a range of sources
such as separate databases within a company
- Aim is to provide suitable storage and tools to be able to extract and
analyse info from huge volumes of data
Data Mining
- The discovery of new patterns in data
- Carried out by software
- Human involvement may include: Selecting and preparing data
sets
Developing data mining software and
algorithms
Interpreting and verifying results
delivered by the data mining software
- Data mining is possible by: Increased power of modern CPUs
Lower cost of hardware
Faster and more efficient
software
Greater availability of data
Database Design
Rules of relational databases:
Data is stored in tables
A table represents a single concept or entity
Each item in one instance of entity is called a record
Each record is made up of attributes of the entity
Database contains one or more tables
Each record must contain a field making the record unique(PK)
PK can be composite (consist of more than one field)
Each record contain a field linking to other tables (FK)
No data field may appear more than once in a table
No field may appear in more than 1 table unless its FK
Normalisation
- Series of steps that need to be followed to ensure databases are
designed correctly
Steps of designing a database:
, - Select the data
- Structure the data
Anomalies
- Insert Design of DB prevents a user from capturing data when
they want to
- Delete Deleting one piece of data results in the simultaneous
removal of other data
- Update When an item of data changes, it has to be altered in
multiple records in the table
The benefits of buying summaries with Stuvia:
Guaranteed quality through customer reviews
Stuvia customers have reviewed more than 700,000 summaries. This how you know that you are buying the best documents.
Quick and easy check-out
You can quickly pay through EFT, credit card or Stuvia-credit for the summaries. There is no membership needed.
Focus on what matters
Your fellow students write the study notes themselves, which is why the documents are always reliable and up-to-date. This ensures you quickly get to the core!
Frequently asked questions
What do I get when I buy this document?
You get a PDF, available immediately after your purchase. The purchased document is accessible anytime, anywhere and indefinitely through your profile.
Satisfaction guarantee: how does it work?
Our satisfaction guarantee ensures that you always find a study document that suits you well. You fill out a form, and our customer service team takes care of the rest.
Who am I buying this summary from?
Stuvia is a marketplace, so you are not buying this document from us, but from seller jaydinbudhoo. Stuvia facilitates payment to the seller.
Will I be stuck with a subscription?
No, you only buy this summary for R50,00. You're not tied to anything after your purchase.
Can Stuvia be trusted?
4.6 stars on Google & Trustpilot (+1000 reviews)
67474 documents were sold in the last 30 days
Founded in 2010, the go-to place to buy summaries for 14 years now