Answers 2026 [Graded A+]
What does Modality refers to? How does it appear on ER diagram? - Answer-Refers to
the MINIMUM number of times an instance in one entity can be associated with
instance of another entity (minima). Appears as a 0 or 1 on the relationship line, next to
cardinality.
Define: Referential Integrity - Answer-Requires that ALL foreign key values must either
be fully NULL or match some primary key value.
4 Ways Referential Integrity can be violated - Answer-1. Primary key is updated 2.
Foreign key is updated 3. Row containing primary key is DELETED 4. Row containing
foreign key is INSERTED.
Actions to Correct Referential Integrity Violation - Answer-1. RESTRICT - rejects an
insert, update, or delete 2. SET NULL - sets invalid foreign keys to null 3. SET
DEFAULT - sets invalid foreign keys to a default primary value 4. CASCADE -
propagates primary key changes to foreign keys.
What is an Important aspect of Referential Integrity - Answer-Reference to data in one
relation is based on values in another relation.
What is Broad definition of data - Answer-Raw facts captured on printed or digital
media.
What Data - Answer-Facts that are collected and stored in a database system.
Determining characteristic of unstructured data - Answer-It does not follow a data
model.
Flat files - Answer-They contain no internal hierarchical organization.
Data retrieval before database management systems - Answer-Sequentially from simple
files.
Primary Key - Answer-An attribute or group of attributes that uniquely identify a tuple in
a relation.
,Foreign Key matching - Answer-A domain of values is necessary for a primary key in
one relation of a database to match with its corresponding foreign key in another
relation of the same database.
partial dependencies - Answer-Dependencies based on only a part of a composite
primary key.
1NF relationship - Answer-A table that has all key attributes defined, no repeating
groups, and all its attributes are dependent on the primary key.
INSERT - Answer-The SQL command that lets you insert data into a table, one row at a
time.
UPDATE - Answer-The SQL command that enables you to make changes in the data.
SELECT * FROM PRODUCT; - Answer-The SQL command used to list all the contents
of the PRODUCT table.
DELETE - Answer-The SQL command used to delete a table row.
LIKE - Answer-A special operator used to check for similar character strings in SQL.
DROP - Answer-The SQL command that can delete a table from the database.
SET columnname = expression - Answer-The command that replaces ***** in the
UPDATE tablename ***** [WHERE conditionlist]; statement.
full outer join - Answer-Returns rows with matching values and includes all rows from
both tables (T1 and T2) with unmatched values.
ETL - Answer-Extract, Transform, Load in database management.
Transformation - Answer-The step in the ETL process where raw data sets are
aggregated.
data extraction - Answer-Extract or copy raw data from multiple sources and store it in a
staging area.
data transformation - Answer-Transform and consolidate the raw data in the staging
area to prepare it for the target data warehouse.
data loading - Answer-Moves the transformed data from the staging area into the target
data storage or warehouse.
, unnormalized forms - Answer-Tables that have repeating groups, contain multi-valued
fields, or fields that contain multiple values.
affinity grouping - Answer-The process of evaluating relationships between data
elements to demonstrate an affinity or link between objects.
Prediction - Answer-Classifies objects according to an expected future behavior.
Load - Answer-The step of the ETL process focused on moving transformed data into
the data warehouse.
Data warehouse - Answer-The primary source of information that feeds analytical
processing for an organization's data analysis.
Increased profitability and increased throughput - Answer-The set of results a company
should expect from implementing a business intelligence system.
Data Mart - Answer-A subject-oriented data repository smaller than a data warehouse,
normally for a smaller or specific group within an organization.
OLAP vs OLTP - Answer-OLAP is for analysis, and OLTP is for transaction processing.
Staging Area - Answer-The infrastructure where raw data sets are aggregated.
Directed Knowledge Discovery - Answer-Knowledge where you have already identified
the problem you want to resolve.
Undirected Knowledge discovery - Answer-Knowledge where you find patterns within
data sets as a way to discover something interesting or an issue.
Classification - Answer-Examine the attributes of a particular object and assign it a
defined class.
Estimation - Answer-The process of assigning continuously valued numeric value to an
object, such as a credit risk assessment.
Clustering - Answer-Task of taking large collections of objects and dividing them into
smaller groups.
Third Normal Form - Answer-When all non-key columns depend on the key, the whole
key, and nothing but the key.
Fact - Answer-A pair of related values in databases.
Boyce-Codd Form - Answer-The same as third normal form except it applies to all key
columns instead of just non-key columns.