case studies Flashcards
case studies
ACID
Atomicity, Consistency, Isolation, Durability. Properties of a database that help guarantee data integrity.
Adobe Flash Player
A web browser plugin which allows a variety of multimedia and interactive content to be included in web pages.
Centralised database
A database in which all data is stored in a single central location.
Distributed database
A database in which data is stored on multiple computers in separate physical locations. Various techniques are used to synchronise the data to prevent data integrity problems.
Client-side software
In a web environment, refers to software that runs in the user’s browser rather than on the web server.
Concurrency
Methods used to ensure multiple (concurrent) operations can be performed on a database without causing data integrity problems. Related to ACID and record locking.
Customer relationship management (CRM) system
A computerised system for managing an organisation’s customer, sales, and marketing information. This might also include customer sales and technical support.
Plug-ins
Software added to web browsers to extend their functionality.
Record locking
Technique used in databases to prevent a record being accessed by more than one user at a time. This prevents data integrity problems (such as a change by one user while another is reading it).
Smartphone
Mobile phone with capabilities typically including Internet access and a camera.
Tablet device
Portable device, often with a touch screen.
Atomicity
Part of ACID. A way of ensuring that database transactions either happen in their entirety, or not at all. For example, a payment from A to B must have money subtracted from person A and credited to person B. Atomicity means either both transactions occur, or neither do.
Consistency
Part of ACID. Ensures that data in a database is always in a consistent state , i.e. that it follows all data validation rules. (Note that this is not the same as being correct).
Isolation
Part of ACID. Ensures that one database transaction cannot unintentionally affect another. For example, two transactions to alter the same record cannot run at the same time.
Durability
Part of ACID. Durability means that once a transaction has occurred, it must ‘stay occurred’, even if the power is lost or the hard disk crashes or there is some other disaster. This typically records a record of all transaction (a transaction log) to be kept.
QR code
Quick Response Code. A type of 2D bar code that can store more data than a regular UPC bar code.
Mail merge
The process of automatically customising a standard letter with individual names and addresses from a database.
Unicode
Encoding system to store text, with support for multiple languages and alphabets, and thousands of characters. Compare ASCII.
CMS
Content Management System. Software which allows management of a web site without web design skills. Content is stored in a database and published in different ways, such as on a web site, in a printed booklet, or in different languages. Sometimes called a WebCMS.
Virtual Private Network
Allows a secure private connection over a public network, using an encrypted ‘tunnel’. For example, a remote computer can securely connect to a LAN, as though it were physically connected.
Comma Separated Values
File format for transferring data, which stores fields and records in a plain text file, separated by commas. See also TSV (Tab Separated Values).
