theory lectures Flashcards
Process Business Model
every department, at different levels, can have information flows with other departments.
Richard Stallman
one of the guru’s of open source.
Give Me Credit licenses
indicate that credit needs to be given when the software is used. if you improve a software you need to give credit to the original creator but you can commercialise it.
Give Me Everything licenses
cannot be commercialised. credit needs to be given for everything.
Open.Office
a project with the aim to reduce Office’s dominant market share.
Linux/Ubuntu
a term given to several operating systems using the Linux code as a foundation.
prototyping
creating prototypes of software applications, ie. incomplete versions of the software program being developed. a prototype simulates only a few aspects and may be different from the final product.
Incremental Build model
the model is designed, implemented, and tested incrementally, meaning a little more is added each time. it is finished when it satisfies all requirements. it combines elements of the waterfall and the iterative philosophy of prototyping.
iterative and incremental development
any combination of both the iterative design and incremental build model. this can be illustrated in a loop. you can go back through the loop.
spiral model
it combines features of prototyping and the waterfall model. it is intended for large, expensive, and complicated projects. it has advantages of both top-down and bottom-up concepts. you start in the middle of the spiral and build outwards.
Rational Unified Process (RUP)
an iterative software development process framework. RUP tried to make software development more structured. It is not a concrete prescriptive process but an adaptable framework, intended to be tailored by the development organisations. You are expected to select elements of the process that are appropriate.
agile
a group of software development methods based on iterative and incremental development. it also focuses on working with the customer.
Scrum
an iterative and incremental agile software development network. it is a flexible, holistic product development strategy. the development team works as an atomic unit, opposing the sequential approach. the idea is to have something to show your client after 2-4 weeks. they ask customers for “stories” when talking about what they want.
product backlog
keeps track of what was done and what needs to be done.
sprint backlog
tells you what needs to be done, but in a sprint. a sprint is a 2-to-4 week cycle.
stand up meeting
usually the form a daily scrum meeting takes. the idea is to move away from the corporate idea of a meeting.
burn down chart
a chart used to keep track of progress. it has total effort on the y-axis and time on the x-axis.
burn up chart
a chart used to keep track of progress. it has story points on the y-axis and time on the x-axis. you can estimate how much time you might need to finish all the story points.
Extreme programming (XP)
has aspects of Scrum. it improves software quality and responsiveness to changing customer requirements. it involves frequent “releases” in short development cycles and introduces checkpoints where new customer requirements can be adopted.
pair programming
programming with two people.
Test-driven development (IDD)
relies on the repetition of a very short development cycle. First, the developer writed an automated test case that defines a desired improvement or new function. then, produces the minimum amount of code to pass that test, and finally refactors the new code to acceptable standards.
Database Management Software (DBMS)
Structured Query Language (SQL)
a non-procedural language. SQL runs in DBMS. it can be embedded into Python and is used for a relational database.
entity
a business object that represents a group, or a category of data. eg. customers, accounts, bank branch.
entity-relationship model (E-R model)
a model of the real world with entities and relationships between entities. it is widely used for database design. every entity gets a table and has columns with attributes. the tables are related to each other and that relationship is held consistent with rules.
cardinality
when the relationship is 1-to-1 or many-to-many.
Entity Relationship Diagram (ERD)
shows how entities are related to one another in a diagram.
junction table
a table with the relationship between different entities. it is only used for complex relationships, otherwise the primary key is added to the entity table.
foreign key
when a primary key is added to an entity table.
instance/record/tuple
a single, specific occurence of an entity.
attribute
a sub-group of information within an entity.
relationship
a link that relates to two entities that share one or more attributes.
primary key
a unique identifier of records in a table. the values may be generated manually or automatically an can consist of more than one field (column).
queries
search the database, fetch information, and display it. this is done using the keyword. they can be made more specific with more lines.
data warehouse
refers to a database that is maintained separately from an organisation’s operational database. it is subject-oriented, integrated, time-variant, and non-volatile collection of data in support of management’s decision-making process. it is based on a multidimensional data model which views data in the form of a cube.
on-line transaction (query) processing (OLTP)
a major task of traditional relational DBMS. day-to-day operations include purchasing, inventory, banking, etc.
on-line analytical processing (OLAP)
a major task of the data warehouse system and includes data analysis and decision-making.
data cube
allows data to be modeled and viewed in multiple dimensions. eg. a company can create a sales data warehouse with dimensions time, item, and location. it can have more dimensions.
star schema
a schema with a fact table in the middle connected to a set of dimension tables. it contains a large central table and a set of smaller attendant tables, one for each dimension.
snowflake schema
a refinement of a star schema where some dimensional hierarchy is further split (normalised) into a set of smaller dimensions, forming a shape similar to a snowflake. However, the snowflake structure can reduce the effectiveness of browsing, since more joins will be needed. It does make your data warehouse less complex.
