"ISDD" Flashcards
insertion anomaly
cannot add info without also doing PK
database validation checks
range check restricted choice length check presence check unique check
what does css stand for
cascading style sheets
pro of using a relational database
removes anomalies
SQL
structured query language
what does it mean if you are information rich
you can access many sources of information like: TV, radio, books, news magazines and can access the www
field name from:
Dog.dogname and criteria = “Olly”
dogname
what does it mean if you are information poor
you tend to not have access to the web and probably find it difficult to access books
-these may be pensioners
modification anomaly
lots of fields may need changing instead of just one
what is an information system
an information system is a combination of hardware and software that can be searched sorted and categorized
deletion anomaly
when something is deleted then something else may also be completely deleted because that may be the only occurrence of that item
what are forms
interfaces through which you can enter information in your database
table name from:
Dog.dogname and criteria = “Olly”
Dog
whats a report
used to summarize and present data in tables in the fastest and easiest readable way possible
characteristic of a poorly designed database
insertion, modification, deletion anomalies.
a complex search
is done on two or more fields
compound key
combines more than one field to make a unique value
a simple search
is done on one field only
search criteria from:
Dog.dogname and criteria = “Olly”
and criteria = “Olly”
whats a query
a request for information from a database that matches a set of criteria
A business is setting up a new communications network. Describe two
implications of the Regulation of Investigatory Powers Act (2000) for this
business.
(Provide facilities) for public authorities (eg police/MI5/ government) to intercept electronic communications OR fit equipment to facilitate surveillance (technical services) OR pay for systems to assist with interception of electronic communications OR pay for the hardware needed to store electronic communication OR inform staff of the fact that access to communication data is subject to the RIPA.
Describe two benefits of prototyping when following a rapid application
development methodology
Allows the client to see/test/ feedback on proposed solutions OR Subsystems/specific elements can be prioritised and tested as early as possible OR A range of proposed solutions can be developed on a small scale instead of the need for full implementation
How do you figure out the range of numbers that can be stored with a set number of bits.
use formula:
2^n - 1
and range is 0 - the result of that calculation above
The more processors present….
The more processors present, the greater the number of tasks that can be processed simultaneously.