SQL (What does it stand for? What is it?)
Structured Query Language (SQL), a database processing language, to query database data
The Internet
... [Show More] (origin info)
the global computer network of networks—was created as the ARPANET in 1969 and then grew and was used to connect all the LANs (and other types of networks).
data
recorded facts and numbers.
POS system
Businesses use point of sale (POS) systems to record every purchase in a database, to monitor inventory, and, if you have a sales promotion card from the store (the one you use to get those special prices for "card holders only"), to keep track of everything you buy for marketing purposes. All the data POS systems gather is stored in, of course, a database.
client-server architecture
A network design in which client computers use a centrally administered server to share data, data storage space, and devices.
USERS use DIVICES on which they have CLIENT applications to access SERVICES. These services are processed by SERVERS, which hold the DATABASES with the data needed (for the client apps).
relational database
A database that represents data as a collection of tables in which all data relationships are represented by common values in related tables
a table
An arrangement of data made up of horizontal rows and vertical columns.
row (def and alternative name)
Each row of a table has data about a particular occurrence, or instance of the thing of interest
also called records
columns (def and alternative name)
Each column of a table stores a characteristic common to all rows
Columns are also known as fields
Each row in a table is uniquely identified by a ______
primary key
what is used to create the relationships between the tables in databases?
the value of primary keys
surrogate key
A system-assigned primary key, generally numeric and auto-incremented.
If the numbers used in primary key columns such as StudentNumber and ClassNumber are automatically generated and assigned in the database itself
composite key
Two or more fields that collectively define the primary key by unique combinations of their values.
When more than one column in a table must be combined to form the primary key
foreign key
A primary key of one table that appears as an attribute in another table and acts to provide a logical relationship between the two tables
information
■ Knowledge derived from data
■ Data presented in a meaningful context
■ Data processed by summing, ordering, averaging, grouping, comparing, or other similar operations [Show Less]