CH6 Flashcards
an organized collection of data.
database
is a group of programs that manipulate the database, and provides an interface between the database and its users and other application programs.
Database management system (DBMS)
T/F: Even without data and the ability to process it, an organization could successfully complete most business activities.
false, could not.
data consists of raw ____.
facts
data must be ______________ to transform it into useful information
organized in a meaningful way
a ____ represents a citcuit that is either on or off.
bit (binary digit)
T/F: a byte is made up of four bits.
false, eight bits.
each byte represents a _____.
character
a name, number or combination of characters that describes an aspect of a business object or activity.
field
a collection of related data fields.
record
a collection of related records.
file
a collection of integrated and related files.
database
bits, characters, fields, records, files, and databases.
hierarchy of data
What is the hierarchy of data? (database/files/records/fields/byte)
database > files > records > fields > byte
a person, place, or thing for which data is collected, stored and maintained.
entity
a characteristic of an entity.
attribute
the specific value of an attribute.
data item
a field or set of fields that uniquely identifies the record.
primary key
In a (traditional/database) approach to data management, information systems share a pool of related data.
database
In a (traditional/database) approach to data management, each distinct operational system used data files dedicated to that system.
traditional
In a database approach to data management, the ability to _____ data and information resources is offered.
share
In a database approach to data management, a ________ is required.
database management system (DBMS)
Summarize in 3 point the Database approach to data management.
- Information systems share a pool of related data
- Offers the ability to share data and information resources
- A database management system (DBMS) is required
What are considerations when building a database (name 6 points)
access, security, archiving, content, logical structure, physical organization.
a diagram of data entities and their relationships.
data model.
data modeling done at the level of the entire enterprise.
enterprise data modeling
data models that use basic graphical symbols to show the organization of and relationships between data.
entity-relationship (ER) diagrams.
a simple but highly useful way to organize data into collections of two-dimensional tables called relations.
relational model
In a relational model, each row in the table represents an _____. And each column represents an _____________.
entity, attribute of that entity.
a range of allowable values for a data attribute.
domain
eliminating rows according to certain criteria.
selecting
eliminating columns in a table.
projecting.
combining two or more tables.
joining
combining two or more tables through common data attributes to form a new table with only the unique data attributes.
linking.