a. index - In database design, a list of keys (or keywords), each of which identifies a
unique record. Indices make it faster to find specific records
b. metadata- data about data
,c. Determinant - is an attribute that can be used to determine the values assigned to other
attributes in the same row
d. Identifier - The database object name for example
e. Key attribute - is the unique characteristic of the entity. For ex. Name and hire date are
attributes of the entity Employee.
f. Constraint - are part of a database schema definition. A constraint is usually associated
with a table and is created with a CREATE CONSTRAINT or CREATE ASSERTION
SQL statement.
a. Database design must reconcile the following requirements:
Design elegance requires that the design must adhere to design rules concerning
nulls, derived attributes, redundancies, relationship types, and so on.
Information requirements are dictated by the end users
Operational (transaction) speed requirements are also dictated by the end users.
Clearly, an elegant database design that fails to address end user information
requirements or one that forms the basis for an implementation whose use
progresses at a snail's pace has little practical use.
b. data independence is the ability of to make changes to data characteristics without
have to make changes to the programs that access the data. It’s important because
, of the savings in time and potential errors caused by reducing modifications to data
access software.
c. Occurs when a relationship is improperly or incompletely identified and, therefore,
is represented in a way that is not consistent with the real world. The most common
design trap is known as a fan trap.
The benefits of buying summaries with Stuvia:
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
You can quickly pay through EFT, credit card or Stuvia-credit for the summaries. There is no membership needed.
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 this summary from?
Stuvia is a marketplace, so you are not buying this document from us, but from seller AcademicFountain. Stuvia facilitates payment to the seller.
Will I be stuck with a subscription?
No, you only buy this summary for R44,36. You're not tied to anything after your purchase.
