module 10# Flashcards
study
(DBMS) database program
software that allows you to create, access, and manage a database.
A primary key
is a field that uniquely identifies each record in a table, such as student ID.
File Processing Systems
In a typical file processing system, each department or area within an organization has its own set of files. The records in one file may not relate to the records in any other file.
Database Approach
When an organization uses a database approach, many programs and users share the data in the database.
The database secures its data so that only authorized users can access certain data items.
The database approach addresses many of the weaknesses associated with file processing systems.
Advantages of the database approach include the following
database service
a website that acts as a portal for a database, enables government agencies, schools, and companies to share information with a wide audience.
Government web database services
can provide access to information about the government as well as information created and used by government agencies.
A field
is a combination of one or more related characters or bytes and is the smallest unit of data a user accesses.
A table
is the highest level in the data hierarchy, as it contains fields and records
A record
is a group of related fields.
A query
extracts data from a database based on specified criteria, or conditions, for one or more fields.
A data dictionary, or a repository
contains data about each table in the database and each field in those tables.
Structured Query Language (SQL or sequel),
a popular query language that allows users to manage, update, and retrieve data.
A query language
consists of simple, English-like statements that allow users to specify the data they want to display, print, store, update, or delete.
QBE (query by example)
a feature that has a graphical user interface to assist users with retrieving data.
A report writer
allows users to design a report on the screen, retrieve data into the report design, and then display or print the report.
A one-to-many relationship (Relational Databases)
connects each record in one table to one or more records in another table.
A one-to-one relationship (Relational Databases)
is restricted to exactly one record in the table on each side of the relationship.
A many-to-many relationship (Relational Databases)
allows more than one record on the left side of the relationship to be connected to more than one record on the right side of the relationship.
Key-value databases
create any number of key-value pairs for each record.
A key-value pair
consists of two related items:
A constant that defines the set (the key)
A variable that belongs to the set (the value)
relational database management system (RDBMS)
a software program in which data is organized as a collection of tables, and relationships between tables are formed through a common field.
A front-end database
is part of a split database that contains the user interface and other objects but not the tables that are needed for an application.
A back-end database,
or the back-end, is part of a split database that contains table objects and is stored on a file server that all users can access
Specially trained database administrators (DBAs)
work with the back-end components to ensure a company’s business data is safe, secure, and well-managed.
An index
is a database object that is created based on a field or combination of fields
Confidentiality, Integrity, and Availability (CIA) triad
Ensuring that data is accessible when it is needed and that no one has made unauthorized changes are key aspects of database security.
A classic security model called the Confidentiality, Integrity, and Availability (CIA) triad addresses these concerns directly.
