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CIS 210 TEST 1
Chapters 1 - 4
48
Computer Science
Undergraduate 2
02/22/2012

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Term
database
Definition
collection of organized data
Term
DBMS
Definition
Database Management System
Term
Database Management System?
Definition
collection of programs that manage database structure and data
Term
data
Definition
raw facts
Term
information
Definition
processed data
Term
record
Definition
row
Term
field
Definition
column
Term
file
Definition
collection of related rows
Term
structural dependence
Definition
file dependent on structure
Term
data redundancy
Definition
data characteristics dependent on structure
Term
data inconsistency
Definition
same data different in another location
Term
update anomaly
Definition
data not updated in both locations
Term
insertion anomaly
Definition
can't add information to one thing because you don't have other information
Term
deletion anomaly
Definition
referencing something that doesn't' exist
Term
Data blocks for data modeling
Definition
entity, relationship, attribute, constraint
Term
entity
Definition
noun object
Term
attribute
Definition
characteristic of entity
Term
relationship
Definition
association of entities
Term
constraint
Definition
restrictions
Term
3 types of relationships
Definition
1:1, M:N, 1:M
Term
business rule
Definition
brief and precise description of a policy
Term
data abstraction levels in data modeling:
Definition
Highest = External, end user
Conceptual, designer
internal, tables
Term
logical independence
Definition
change of the internal model without effecting the conceptual model (change int to string)
Term
physical independence
Definition
change in physical model without effecting internal model (change algorithms)
Term
primary key
Definition
unique
Term
foreign key
Definition
unique key in one table referencing a table it's a primary key in
Term
super key
Definition
any key that uniquely identifies each row
Term
candidate key
Definition
a super key without unnecessary attributes
Term
composite key
Definition
composed of more than one atrribute
Term
entity integrity
Definition
value must be unique and must not be null
Term
referential integrity
Definition
if value of foreign key is not null, then the value must exist in the table it references
Term
SELECT
Definition
selects a group of rows that satisfy the condition
Term
PROJECT
Definition
selects distinct attributes fro a table
Term
UNION
Definition
combines rows from two tables
(union-compatible)
Term
INTERSECT
Definition
includes all rows that are in both tables
(union-compatible)
Term
DIFFERENCE
Definition
includes all rows that are in the first table, but not the second
(union-compatible)
Term
PRODUCT (CARTESIAN PRODUCT)
Definition
includes all possible pairs
Term
JOIN
Definition
combines related rows from two tables into single table
Term
Inner Join
Definition
only returns matched rows being joined
Term
Outer Join
Definition
matched pairs will be retained, any unmatched values in the other table will be left null
Term
Left Outer Join
Definition
keeps everything in left table
Term
Right Outer Join
Definition
keeps everything in right table
Term
Full Outer Join
Definition
Keeps everything.
Term
DIVIDE
Definition
result of a single attribute table with the values of attribute "a" from the dividend relation rows where the value of "b" in both relations
Term
2 conditions that must be met before an entity can be classified as weak
Definition
existent dependent and the PK must be derived or partially derived from an entity
Term
recursive relationship
Definition
a relationship only related to ssingle
Term
derived attribute
Definition
entity whose attribte can be derived
Term
composite entity
Definition
bridges a (m:n) relationship
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