Fluency with Information Technology Chapter 15

databases are thought of as

tables of information

metadata tagging scheme

extensible markup language (XML)

root element

the tag that encloses all content in the XML file

identification rule

consistently use tags to label data

affinity rule

data that references an entity should be grouped together

collection rule

group instances together

entities

rows at a database table

attribute name

column heading

entity instance

the value in a row

table instance

the whole table

database tables can also be known as

relations

a column that uniquely identifies every entry is called a

candidate key

locate unique entries during database operations, a type of candidate key called a

primary key

a database table’s metadata is known as a

database key

the database system is instructed to a compute an answer by manipulating the table information through a command called a

query

the most widely used language for databases

Structured Query Language, or SQL

the storage of data to the disk drive of a computer system, which is the permanent repository

physical database

view of the database which is created and changeable based on the needs of the user

logical database