Study Guide for Midterm

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Study Guide for Mid-term
CPSC260
Data, Information and Knowledge – understand the differences, be able to give
original examples.
To be useful, data must be: accurate, relevant and timely. Be able to explain why
for each of these characteristics of data.
Meta-data/data dictionary
Advantages of DBMS - pg. 7
Functions of a DBMS – pg. 20
Structural and data dependence and independence
Logical data format and physical data format
Anomalies
Update, Insert and Delete – be able to explain
Parts of a database system from a general management point of view (5 parts)
Relationships
One-to-one, One-to-Many, Many-to-Many – be able to give an example of
each and to model using ERD.
Business rule – what is its role in database design?
Relational model – table based representation of data
Characteristics of a Relational Table – Table 3.1 on pg. 62
Keys
Concept of determination and functional dependence
Superkey, candidate key, primary key, secondary key, composite key, foreign
key, surrogate key
Integrity rules
Entity integrity, Referential integrity – understand how to determine if a
particular table or group of tables have entity and referential integrity
Relational Set Operations
Understand and be able to perform Select, Project, Join, Product operations
Understand the difference between a natural and a left or right outer join
operation
Understand how to represent 1:1 and 1:M relationships in relational tables
Understand how to convert one M:N relationship into two 1:M relationships using a
bridge entity
Index, unique index – what are these and when would they be used in the design of
a database?
Multi-valued attributes – what are they and how can they be included into a
database design (2 alternatives)
Derived attributes – what are they and what is the tradeoff that needs to be
considered with respect to derived attributes?
Existence dependence – give an example of two entities in which one entity is
existence dependent on the other
Strong and weak relationships / identifying and non-identifying relationships –
understand the difference in the way they are represented on an ERD diagram
Weak and Strong entities
Optional and Mandatory relationships – how are these represented on an ERD?
Normalization – if presented with a table, be able to determine which, if any,
normal form it is in. (Must understand the conditions necessary for each of
the normal forms 1NF, 2NF and 3NF. Don’t need to know BCNF or 4NF)
Also, need to be able to convert a table not in normal form to 1NF, a 1NF
table to 2NF, and a 2NF table to 3NF.
Understand database design considerations beyond normal forms:
Evaluating the primary key (determine if a surrogate key should be used)
Attribute atomicity
Maintaining historical accuracy
Evaluate use of derived attributes
Understand what denormalization is and why you might make a decision to
denormalize a table in a design.
Authorization and Authentication – how might the data required for these system
functions be modeled in a database design. (Hint: Covered this in class.
Information is not in the book).
What is a domain table? What is it used for? Give an example. (Hint: Covered this
in class. Information is not in the book).
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