100% satisfaction guarantee Immediately available after payment Both online and in PDF No strings attached
logo-home
ISA 245 Exam 2 With 100% Correct And Verified Answers $17.99   Add to cart

Exam (elaborations)

ISA 245 Exam 2 With 100% Correct And Verified Answers

 6 views  0 purchase
  • Course
  • ISA 245
  • Institution
  • ISA 245

ISA 245 Exam 2 With 100% Correct And Verified Answers

Preview 3 out of 16  pages

  • September 2, 2024
  • 16
  • 2024/2025
  • Exam (elaborations)
  • Questions & answers
  • fourth normal form 4nf
  • ISA 245
  • ISA 245
avatar-seller
Vendarsol
ISA 245 Exam 2 With 100% Correct And
Verified Answers 2024-2025
Boyce-Codd Normal Form (BCNF) - Correct Answer-A special type
of third normal form (3NF) in which every determinant is a
candidate key.

Candidate key - Correct Answer-An attribute, or combination of
attributes, that uniquely identifies a row in a relation.

Fourth Normal Form (4NF) - Correct Answer-In 3NF and contains
no multiple independent sets of multivalued dependencies.

surrogate key - Correct Answer-A system-assigned primary key,
generally numeric and auto-incremented.

De-normalization - Correct Answer-The process of splitting or
combining normalized relations into physical tables based on
affinity of use of rows and fields. (intentionally adds redundancy)

Why do we need to consider de-normalization? - Correct Answer-
improves query performance, processing speed, makes reports
easier

multivalued attribute - Correct Answer-An attribute that may take
on more than one value for a given entity (or relationship)
instance.

Data Definition Language (DDL) - Correct Answer-DBMS language
that builds the data dictionary, creates the database, describes
logical views, and specifies record or field security constraints
(ex. creating a table, creating a view, etc.)

Vendarsol

,Data Manipulation Language (DML) - Correct Answer-DBMS
language that changes database content, including data element
creations, updates, insertions, and deletions (SELECT, UPDATE,
INSERT, DELETE, COMMIT, ROLLBACK)

Can you update a constraint? - Correct Answer-NO! We must drop
the constraint and add a new one instead

Adding new constraints - Correct Answer-ALTER TABLE
tablename
ADD (constraint)
CHECK

Inserting a record - Correct Answer-INSERT INTO table VALUES()

rowid - Correct Answer-internally assigned by the system

DROP vs DELETE. - Correct Answer-DROP: DDL that affects the
schema and cannot be rolled back. Deletes the entire table!

DELETE: DML that affects the data only and can be rolled back.
Deletes only the contents of the table while maintaining the
structure

COUNT(*) vs COUNT - Correct Answer-Count
all values, including null
Count just the non-null values

disable - Correct Answer-make unable to
perform a certain action



Vendarsol

, entity supertype - Correct Answer-A generic
entity type that contains the common
characteristics of the entity subtypes.

entity subtype - Correct Answer-contain the
unique characteristics of each entity

entity supertype vs entity subtype - Correct
Answer-A subtype is the subset of the entity
supertype. The supertype is more common
characteristics and the subtype is more
unique characteristics

specialization hierarchy - Correct Answer-
based on grouping unique characteristics and
relationships of entity subtypes

entity cluster - Correct Answer-temporary
entity used to represent groups of related
entities and relationships within a database
model. ("virtual" or "abstract" -not a real
entity type in the final ERD)

Why do we sometimes need to use entity
cluster in an ER diagram? - Correct Answer-
simplifies the ERD and enhances its
readability




Vendarsol

The benefits of buying summaries with Stuvia:

Guaranteed quality through customer reviews

Guaranteed quality through customer reviews

Stuvia customers have reviewed more than 700,000 summaries. This how you know that you are buying the best documents.

Quick and easy check-out

Quick and easy check-out

You can quickly pay through credit card or Stuvia-credit for the summaries. There is no membership needed.

Focus on what matters

Focus on what matters

Your fellow students write the study notes themselves, which is why the documents are always reliable and up-to-date. This ensures you quickly get to the core!

Frequently asked questions

What do I get when I buy this document?

You get a PDF, available immediately after your purchase. The purchased document is accessible anytime, anywhere and indefinitely through your profile.

Satisfaction guarantee: how does it work?

Our satisfaction guarantee ensures that you always find a study document that suits you well. You fill out a form, and our customer service team takes care of the rest.

Who am I buying these notes from?

Stuvia is a marketplace, so you are not buying this document from us, but from seller Vendarsol. Stuvia facilitates payment to the seller.

Will I be stuck with a subscription?

No, you only buy these notes for $17.99. You're not tied to anything after your purchase.

Can Stuvia be trusted?

4.6 stars on Google & Trustpilot (+1000 reviews)

67866 documents were sold in the last 30 days

Founded in 2010, the go-to place to buy study notes for 14 years now

Start selling
$17.99
  • (0)
  Add to cart