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~The Communication Framework Model~








~Issues Related to Information Systems and Databases~

Acknowledgement of Data Sources
The reasons for acknowledging data sources which includes justifying and verifying outputs, auditing and tracking the accuracy of data and complying with requirements of the data source organisation/individual.

The Freedom of Information Act
An act to give members of the public rights of access to official documents of the Government of the Commonwealth and of its agencies.

Privacy Principles (National Privacy Principles)

• NPP 1: Collection


• NPP 2 Use and Disclosure


• NPP 3 & 4: Information Quality and Security


• NPP 5: Openness


• NPP 6: Access and Correction


• NPP 7: Identifiers


• NPP 8: Anonymity


• NPP 9: Trans border Data Flows


• NPP 10: Sensitive Information

Quality of Data

A general term that describes the quality and reliability of data and is synonymous with "data integrity". It can be improved with use of "data validation" and "data verification".

~Search Engines~

Free Text Searching
Searching for the occurrence of one or more words within a passage or page (E.g. CTRL + F)

Operations of a Search Engine

• Web Directories- Where humans categorise a verbiage based on information supplied by the creator (E.g.Catherine McAuley could be added to Google using the "add URL Service" and categorised under "education")


• Meta Search Engines- Sites that submit search criteria to multiple search engines and then compile the results

Meta Data

Data about data and includes all HTML tags and the specific Meta tags that hold page title and keyword summaries.

~Centralised & Distributed Databases~

There are THREE strategies involved with centralised and distributed databases. These are as follows:

1. Fragmentation- Parts of a database are stored in different location with each item only stored once. During queries data may be transferred from a remote location. This requires a fast and reliable connection.
E.g. Each example only occurs at one location
ABC DEF GHI

2. Downloading- Each server downloads copies as required, hence with frequently used data, copies will be located on the local server. This is suited to data that rarely changes and has a fast access time.
E.g. All location have copies of data D and E
ABCDE DEF GHIDE

3. Replication- Uses master and replicant databases. Local databases hold copies of all data of the time (goal). Local replicant databases are constantly updating with the master database, which usually takes place at night and does not require a fast connection.
E.g. Ideally complete copies occur at each location (the same)
ABCDEFGHI ACDEFGHI ACDEFGHI

~Hypermedia~

Hypertext- Bodies of text linked in a non-sequential manner where each box contains links to other boxes of text
Hypermedia- Extension of hypertext to include images and videos
Nodes- A point where links are connected (e.g. web page)

Storyboards

• A technique that was first used for the creation of video information, including film, television and animation
• Contains purpose, contents and elements
• Shows navigation in structure

Linear Navigation

• Simple form of navigation
• Not much options or choices to be made
• One path

Hierarchical Navigation

• Organised structure
• Not overwhelmed by information
• No link between categories
• Stops unnecessary information

Non-Linear Navigation

• Easy for the user to get lost
• Often need to provide a site map

Composite Navigation

• Most hypertext websites use composite
• Form a sequence

~Normalisation~

Advantages of Normalisation

• Takes up less space as it removes data redundancy
• Allows for faster querying due to less data being processed

First Normal Form (1NF)

• Each filed stores data items
• If data items can be separated, then separate them
• No multiple data items within individual fields and no fields are repeated

Second Normal Form (2NF)

• All tables must comply with 1NF (nothing is repeated)
• Non-key attributes (not unique) are functionally dependent on the primary key (e.g. stud ID 001 is smith but stud ID 002 is also smith but a DIFFERENT smith)
• The primary key defines only ONE non-key attribute although doesn't have to be unique
• Example: date of birth, address, etc are all functionally dependent on the student ID

Third Normal Form (3NF)

• All tables must comply with 1NF and 2NF
• Every non-key attribute is functionally dependent only on the set table's primary key

~Relational Databases~

• The most commonly used type of database that consists of multiple tables that store particular sets of data which are related to each other hence the name.
• Every table is divided into a series of records where each has a designated key field used to sort, index and link data between tables
• The schema shows an overall view of the data and of the relationships between tables
• Data can be viewed for different purposes according to search, queries or reports that are run

Part of a Relational Database

• Entity- Is a topic or specific thing about which information is being collected.
• Attribute-A defined property of an entity (same thing as fields in a flat file database).
• Key Field- Any field that can be used to sort the data is a 'key field' as opposed to the primary key which is a designated field. A key is is an entity in a table that distinguishes a row of data from another or a single column or group of columns uniquely identifying a record.
• Primary Key- Unique fields that can be an individual attribute or a combination of them but must not be null. (e.g. composite key)
• Foreign Key- The primary key of another table and relate tables in the database to each other. A foreign key in one table is a primary key in another and vice versa.
• Table- Information about an entity is stored in tables containing columns and rows. A row in a table is called a tuple of an entity and represents a record and a column is called the attribute. Tables relate to data contained in other tables.

Relationships


Refers to the link between the various tables and is usually made through a primary key in the primary table linking through to a field in a secondary table. There are four types of relationships:

• One-to-One: Occurs when the primary key in one table is linked to the primary key in another, meaning that the primary key in both tables are identical. These aren't very common and achieve very little.
• One-to-Many: Used to relate one relationship to one record in a table with many records in another. These are the most common and most practical for the majority of applications.
• Many-to-One: Involves a lookup table taking the place of the primary key.
• Many-to-Many: A pair of one to many relationships between two tables (e.g. students will have many classes and many classes will have many students)

This is an example of a schema:

~The Communication Framework Model~








~Issues Related to Information Systems and Databases~

Acknowledgement of Data Sources
The reasons for acknowledging data sources which includes justifying and verifying outputs, auditing and tracking the accuracy of data and complying with requirements of the data source organisation/individual.

The Freedom of Information Act
An act to give members of the public rights of access to official documents of the Government of the Commonwealth and of its agencies.

Privacy Principles (National Privacy Principles)

• NPP 1: Collection


• NPP 2 Use and Disclosure


• NPP 3 & 4: Information Quality and Security


• NPP 5: Openness


• NPP 6: Access and Correction


• NPP 7: Identifiers


• NPP 8: Anonymity


• NPP 9: Trans border Data Flows


• NPP 10: Sensitive Information

Quality of Data

A general term that describes the quality and reliability of data and is synonymous with "data integrity". It can be improved with use of "data validation" and "data verification".

~Search Engines~

Free Text Searching
Searching for the occurrence of one or more words within a passage or page (E.g. CTRL + F)

Operations of a Search Engine

• Web Directories- Where humans categorise a verbiage based on information supplied by the creator (E.g.Catherine McAuley could be added to Google using the "add URL Service" and categorised under "education")


• Meta Search Engines- Sites that submit search criteria to multiple search engines and then compile the results

Meta Data

Data about data and includes all HTML tags and the specific Meta tags that hold page title and keyword summaries.

~Centralised & Distributed Databases~

There are THREE strategies involved with centralised and distributed databases. These are as follows:

1. Fragmentation- Parts of a database are stored in different location with each item only stored once. During queries data may be transferred from a remote location. This requires a fast and reliable connection.
E.g. Each example only occurs at one location
ABC DEF GHI

2. Downloading- Each server downloads copies as required, hence with frequently used data, copies will be located on the local server. This is suited to data that rarely changes and has a fast access time.
E.g. All location have copies of data D and E
ABCDE DEF GHIDE

3. Replication- Uses master and replicant databases. Local databases hold copies of all data of the time (goal). Local replicant databases are constantly updating with the master database, which usually takes place at night and does not require a fast connection.
E.g. Ideally complete copies occur at each location (the same)
ABCDEFGHI ACDEFGHI ACDEFGHI

~Hypermedia~

Hypertext- Bodies of text linked in a non-sequential manner where each box contains links to other boxes of text
Hypermedia- Extension of hypertext to include images and videos
Nodes- A point where links are connected (e.g. web page)

Storyboards

• A technique that was first used for the creation of video information, including film, television and animation
• Contains purpose, contents and elements
• Shows navigation in structure

Linear Navigation

• Simple form of navigation
• Not much options or choices to be made
• One path

Hierarchical Navigation

• Organised structure
• Not overwhelmed by information
• No link between categories
• Stops unnecessary information

Non-Linear Navigation

• Easy for the user to get lost
• Often need to provide a site map

Composite Navigation

• Most hypertext websites use composite
• Form a sequence

~Normalisation~

Advantages of Normalisation

• Takes up less space as it removes data redundancy
• Allows for faster querying due to less data being processed

First Normal Form (1NF)

• Each filed stores data items
• If data items can be separated, then separate them
• No multiple data items within individual fields and no fields are repeated

Second Normal Form (2NF)

• All tables must comply with 1NF (nothing is repeated)
• Non-key attributes (not unique) are functionally dependent on the primary key (e.g. stud ID 001 is smith but stud ID 002 is also smith but a DIFFERENT smith)
• The primary key defines only ONE non-key attribute although doesn't have to be unique
• Example: date of birth, address, etc are all functionally dependent on the student ID

Third Normal Form (3NF)

• All tables must comply with 1NF and 2NF
• Every non-key attribute is functionally dependent only on the set table's primary key

~Relational Databases~

• The most commonly used type of database that consists of multiple tables that store particular sets of data which are related to each other hence the name.
• Every table is divided into a series of records where each has a designated key field used to sort, index and link data between tables
• The schema shows an overall view of the data and of the relationships between tables
• Data can be viewed for different purposes according to search, queries or reports that are run

Part of a Relational Database

• Entity- Is a topic or specific thing about which information is being collected.
• Attribute-A defined property of an entity (same thing as fields in a flat file database).
• Key Field- Any field that can be used to sort the data is a 'key field' as opposed to the primary key which is a designated field. A key is is an entity in a table that distinguishes a row of data from another or a single column or group of columns uniquely identifying a record.
• Primary Key- Unique fields that can be an individual attribute or a combination of them but must not be null. (e.g. composite key)
• Foreign Key- The primary key of another table and relate tables in the database to each other. A foreign key in one table is a primary key in another and vice versa.
• Table- Information about an entity is stored in tables containing columns and rows. A row in a table is called a tuple of an entity and represents a record and a column is called the attribute. Tables relate to data contained in other tables.

Relationships


Refers to the link between the various tables and is usually made through a primary key in the primary table linking through to a field in a secondary table. There are four types of relationships:

• One-to-One: Occurs when the primary key in one table is linked to the primary key in another, meaning that the primary key in both tables are identical. These aren't very common and achieve very little.
• One-to-Many: Used to relate one relationship to one record in a table with many records in another. These are the most common and most practical for the majority of applications.
• Many-to-One: Involves a lookup table taking the place of the primary key.
• Many-to-Many: A pair of one to many relationships between two tables (e.g. students will have many classes and many classes will have many students)

This is an example of a schema:

Marielle.
cmac12'er

dennieljustin.`220710

&& im just awesomer than you. ;D

year 12 IPT home
two.
three.
four.
five.