My Midterm Questions - CIST1220 - Structured Query Language-SQL
What do you create when you transform a Many-to-Many relationship from your ER diagram into a physical design? A) Intersection table B) Foreign key constraints C) Intersection entity D) Primary key constraints
A) Intersection table
A column represents a field in the physical database table. A) True B) False
A) True
A recursive relationship should not be part of a UID. True or False?
A) True
A table does not have to have a primary key. True or False?
A) True
All attributes that are part of the UID are mandatory. True or False? A) True B) False
A) True
If subtypes are listed, a supertype should have at least two subtypes. True or False? A) True B) False
A) True
SELECT *FROM employees;This statement will retrieve all the rows in the employees table. True or False?
A) True
The demand for Information Technology professionals in today's market is increasing. A) True B) False
A) True
The simplest approach to remove a partial dependency is to use each portion of the primary key to create separate tables. A) True B) False
A) True
Two tables can be linked or joined together through a common field. A) True B) False
A) True
A field in the logical design of a database is represented by what in the physical database? A) column B) row C) field D) row
A) column
In an E-R Model a person, place, or thing with characteristics to be stored in the database are referred to as? A) entity B) row C) attribute D) file
A) entity
A Matrix Diagram will help you with all of the following except: A) Naming Relationships B) Defining Instances of Entities C) Identifying Entities D) Verifying Relationships Between Entities
B) Defining Instances of Entities
Unique Identifiers: A) Distinguish one entity from another B) Distinguish one instance of an entity from all other instances of that entity C) Distinguish nothing D) Distinguish all entities in a database
B) Distinguish one instance of an entity from all other instances of that entity
A database is a physical storage device for data. A) True B) False
B) False
A unique identifier can only be made up of one attribute. True or False? A) True B) False
B) False
An entity can be on 2nd Normal Form even if it has repeated values. True or False? A) True B) False
B) False
Creating a Matrix Diagram is a mandatory step in Data Modeling. True or False?
B) False
Data Modeling is the last step in the database development process. True or False?
B) False
Data is in second normal form (2NF) if it contains no repeating groups and has a primary key to uniquely identify each record. A) True B) False
B) False
Data redundancy is created through a process known as normalization. A) True B) False
B) False
No formal rules exist for drawing ERD's. The most important thing is to make sure that all entities, attributes, and relationships are documented on the diagram. The Layout is insignificant. True or False?
B) False
One or more columns in a primary key can be null. True or False?
B) False
One-to-One relationships are transformed into Foreign Keys in the tables created at either end of that relationship. True or False?
B) False
Personal computers (PCs) have been in existence since 1950. True or False?
B) False
Relationships on an ERD can only be transformed into UIDs in the physical model? True or False?
B) False
When reading a relationship between 2 entities, the relationship is only read from left to right. True or False?
B) False
A customized hat sitting on your friend's head is an example of which model--the conceptual model or the physical model? A) Conceptual Model B) Physical Model
B) Physical Model
In a physical data model, an entity becomes a/an _____________. A) Constraint B) Table C) Column D) Attribute
B) Table
Why would you want to model a time component when designing a system that lets people buy bars of gold? A) You would not want to model this; it is not important. B) The price of gold fluctuates and, to determine the current price, you need to know the time of purchase. C) Sales people must determine where the gold is coming from. D) The Government of your country might want to be notified of this transaction.
B) The price of gold fluctuates and, to determine the current price, you need to know the time of purchase.
Analyzing historical sales data stored in a database is commonly referred to as ____. A) data storage B) data mining C) data manipulation D) archived data
B) data mining
A foreign key is usually found on which side of a relationship? A) one B) many C) unnormalized D) primary entity
B) many
Which of the following terms represents a collection of fields? A) field B) record C) character D) file
B) record
How do you turn "data" into "information"? A) By testing it B) By storing it on a server C) By querying it or accessing it D) By storing it in a database
C) By querying it or accessing it
Which of the following may contain transitive dependencies, but not partial dependencies? A) unnormalized data B) first normal form (1NF) C) second normal form (2NF) D) third normal form (3NF)
C) second normal form (2NF)
Relationships always exist between A) 3 or more attributes B) 3 or more entities C) 2 attributes D) 2 entities (or one entity and itself)
D) 2 entities (or one entity and itself)
Which of the following is the best scenario for using supertype/subtype entities: A) A grocery store that gives customers a choice of plastic or paper bags B) An ice cream store that sells ice cream in sugar cones and regular cones C) A pet store that sells small animals that need different sized cages and different food D) A vehicle dealership that sells boats on trailers, cars, and trucks
D) A vehicle dealership that sells boats on trailers, cars, and trucks
The data model can be used to __________. A) Communicate and group B) Describe and specify C) Analyze and copy D) All of the Above
D) All of the Above
Which of the following would be a logical constraint when modeling time for a country entity? A) Daily traffic patterns must be monitored to determine which countries are overcrowded. B) People have births and deaths in their countries that must be tracked by the system. C) If you are doing a system for France or Germany, you would need security clearance. D) Countries may change their names and/or borders over a period of time.
D) Countries may change their names and/or borders over a period of time.
A non-transferable relationship is represented by which of the following symbols? A) Heart B) Triangle C) Circle D) Diamond
D) Diamond
During which phases of the System Development Life Cycle would you roll out the system to the users? A) Build and Transition B) Strategy and Analysis C) Design and Production D) Transition and Production
D) Transition and Production
The explanation below is an example of which constraint type? If the value in the balance column of the ACCOUNTS table is below 100, we must send a letter to the account owner which will require extra programming to enforce. A) Entity integrity B) Referential integrity C) Column integrity D) User-defined integrity
D) User-defined integrity
When are relationships unnecessary? A) When the relationships connect 2 entities and they each have distinct meanings B) When the information does not relate to the model C) When they have the same visual structure but different meaning D) When you can derive the relationship from other relationships in the model
D) When you can derive the relationship from other relationships in the model
A ____ is a group of interrelated files. A) record B) character C) field D) database
D) database
If you want to see just a subset of the columns in a table, you use what symbol? A) & B) % C) * D) instead of using a symbol, you name the columns for which you want to see data.
D) instead of using a symbol, you name the columns for which you want to see data.
Which of the following are reasons we create conceptual models? A) It facilitates discussion; a picture is worth a thousand words B) It forms important ideal system documentation C) It takes into account government regulations and laws D) It forms a sound basis for physical database design E) All of the above
E) All of the above