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Section 2 Quiz (Answer all questions in this section) 1. Capturing all required data is the only goal of entity relationship modeling.

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True False (*)

Incorrect. Refer to Section 2 Lesson 6. 2. An ERD created using ERDish is a __________ representation of entities and their relationships to each other.

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graphical (*) textual technical hierarchical

Incorrect. Refer to Section 2 Lesson 6. 3. ERDish includes the following except:

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Optionality Data Values. (*) Relationship Names Cardinality

Incorrect. Refer to Section 2 Lesson 5. 4. A foreign key is a column or combination of columns in one table that uniquely identifies a row of another table.

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True (*) False

Correct

5. A relationship is transformed from logical to physical model using _________.

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Foreign Keys (*) Composite Keys Secondary Keys Candidate Keys 6. If a relationship is mandatory there must be at least one instance of the corresponding entity related to it.

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True (*) False

Correct 7. The physical model shows all table structures. True or False.

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True (*) False

Correct 8. The logical model determines relationship optionality and cardinality

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True (*) False

Correct 9. The primary key uniquely identifies each row in a table and is based on the __________ from the logical design.

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Secondary UID Candidate UID Composite UID Primary UID (*)

Incorrect. Refer to Section 2 Lesson 4. 10. All entities must be given a new artificial UID. True or False?

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True False (*)

Incorrect. Refer to Section 2 Lesson 4. 11. Each column in a relation is called an entity. True or False?

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True False (*)

Correct 12. What does single table refer to? (Choose Two)

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(Choose all correct answers) A type of database storage method where all of the data elements are stored on top of each other. Non-relational systems that typically store each table and index in separate files and often do not support the SQL language. (*) A fully-relational database system like Microsoft's SQL Server or Oracle's database systems. A database where all of the data is stored in one large table. (*)

Correct

13. In this course, we use the __________ notation for ERD modeling.

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Bachman Barker (*) Information Engineering None of the above

Incorrect. Refer to Section 2 Lesson 3. 14. To identify an attribute as part of a unique identifier on an ER diagram, the # symbol goes in front of it. True or False?

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True (*) False

Incorrect. Refer to Section 2 Lesson 3. 15. Which of the attributes is a volatile attribute?

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Eye color Age (*) Race Date of birth

Incorrect. Refer to Section 2 Lesson 3.

1. Identify all of the incorrect statements that complete this sentence: A primary key is...(Choose three)

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(Choose all correct answers) Only one column that must be null. (*) One or more columns in a table that uniquely identifies each row in that table. A set of columns in one table that uniquely identifies each row in another table. (*) A single column that uniquely identifies each column in a table. (*) Incorrect. Refer to Section 2 Lesson 1. 2. In the relational model, relationships between relations or tables are created by using?

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Foreign Keys (*) Primary Keys Candidate Keys Composite Keys Correct 3. One-to-One relationships have

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_____________ of one to one in both directions. Naming Cardinality (*) Optionality Foreign Keys

Incorrect. Refer to Section 2 Lesson 5. 4. A foreign key is a column or combination of columns in one table that uniquely identifies a row of another table.

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True (*) False

Correct 5. A __________ relationship is a relationship between an entity and itself. Hierarchical Mandatory One to one Recursive (*) Incorrect. Refer to Section 2 Lesson 5.

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6. The primary key uniquely identifies each row in a table and is based on the __________ from the logical design.

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Composite UID Secondary UID Primary UID (*) Candidate UID

Correct 7. Unique Identifiers…

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Distinguish all entities in a database Distinguish nothing Distinguish one instance of an entity from all other instances of that entity (*) Distinguish one entity from another.

Correct 8. Which of the following is not a goal of ER modeling:

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Locate information in a logical manner Capture all required information. It is acceptable to include information that is derivable. (*) Ensure information appears only once.

Incorrect. Refer to Section 2 Lesson 6. 9. A model is considered to be Implementation-Free if it can be implemented using ____ of the database software models such as hierarchical, network or relational.

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any (*) only one none

Incorrect. Refer to Section 2 Lesson 6. 10. Data models are drawn to show users the actual Data that their new system will contain; only Data listed on the Diagram can be entered into the Database. True or False?

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True False (*)

Incorrect. Refer to Section 2 Lesson 6.

11. The logical model determines relationship optionality and cardinality

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True (*) False

Correct 12. A conceptual model includes :

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Only Entities, Attributes and Unique Identifiers Entities, Attributes, Unique Identifiers and Relationships Only Entities, Attributes and Relationships Only Entities and Relationships (*)

Incorrect. Refer to Section 2 Lesson 2. 13. Attributes have Instances. True or False?

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True

False (*)

Correct 14. Entity names are always singular. True or False?

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True (*) False

Incorrect. Refer to Section 2 Lesson 3. 15. Entities are usually _____________.

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Verbs Adverbs Adjectives Nouns (*)

Incorrect. Refer to Section 2 Lesson 3.

1. To identify an attribute as part of a unique identifier on an ER diagram, the # symbol goes in front of it. True or False?

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True (*) False

Correct 2. Which symbol is used to show that a particular attribute is optional?

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o (*) # * &

Incorrect. Refer to Section 2 Lesson 3. 3. Which of the following entities most likely contains invalid attributes?

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Entity: Car. Attributes: Owner Occupation, Owner Salary, Speed (*) Entity: Home. Attributes: Number of Bedrooms, Owner, Address, Date Built Entity: Pet. Attributes: Name, Birthdate, Owner Entity: Mother. Attributes: Name, Birthdate, Occupation, Number of Children

Correct

4. Primary keys can contain null values.

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True False (*)

Correct 5. A Unique Identifier has a NULL value for each instance of the entity for the lifetime of the instance. True or False

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True False (*)

Correct

6. Which of the following statements is true regarding ImplementationFree logical models?

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The model changes depending on operating system that is being used. The model changes depending on the relational database software being used The model does not need to implemented on a DBMS. The model stays the same regardless of the DBMS or operating system used. (*) Incorrect. Refer to Section 2 Lesson 6. 7. When mapping a relationship for an ERD relationship names must be included.

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True (*) False

Correct

8. ERDish includes the following except:

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Optionality Cardinality Relationship Names Data Values. (*)

Correct 9. The physical model shows all table structures. True or False.

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True (*) False

Correct 10. The logical model's entities, attributes, unique identifiers and relationships map to the physical model's _________________.

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Optionality and Cardinality Files, records, fields and data values Tables, columns, primary keys and foreign keys (*)

Correct

11. Flat file databases are generally in plaintext form, where each line holds only one record. True or False?

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True (*)

False

Incorrect. Refer to Section 2 Lesson 1. 12. By defining ________ and _____ keys, you can ensure that the integrity of the data in a table is maintained.

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primary, foreign (*) foreign, unique primary, secondary primary, unique

Correct 13. Which of the following is NOT an example of cardinality?

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All are examples of cardinality. How many types of jobs are there? (*) How many employees can hold one specific job? How many jobs can one employee hold?

Incorrect. Refer to Section 2 Lesson 5. 14. A relationship can be between ____________.

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two entities an entity and itself multiple entities All of the above. (*)

Correct 15. The cardinality of a relationship can be _____________. (Choose two)

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(Choose all correct answers)

one or more (*) one to one many to many one and only one (*)

Incorrect. Refer to Section 2 Lesson 5.

1. A relational database stores information in tables with rows and columns.

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True (*) False

Correct 2. In the relational model, relationships between relations or tables are created by using?

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Foreign Keys (*) Candidate Keys Composite Keys Primary Keys

Correct 3. In this course, we use the __________ notation for ERD modeling.

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Bachman Barker (*) Information Engineering None of the above

Correct

4. When creating entities in a logical model you must follow these rules: (Choose Two)

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(Choose all correct answers) Include Attributes (*) Name them in Plural Exclude Attributes Name them in Singular (*)

Incorrect. Refer to Section 2 Lesson 3. 5. An entity may have which of the following?

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Experiences Instances (*) Tables None of the above

Correct

1. A relational database stores information in tables with rows and columns.

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True (*) False

Correct 2. In the relational model, relationships between relations or tables are created by using?

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Foreign Keys (*) Candidate Keys Composite Keys Primary Keys

Correct 3. In this course, we use the __________ notation for ERD modeling.

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Bachman Barker (*) Information Engineering None of the above

Correct 4. When creating entities in a logical model you must follow these rules: (Choose Two)

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(Choose all correct answers) Include Attributes (*) Name them in Plural Exclude Attributes Name them in Singular (*)

Incorrect. Refer to Section 2 Lesson 3. 5. An entity may have which of the following?

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Experiences Instances (*) Tables None of the above

Correct

6. An ERD is an example of a ______ Model.

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Physical Network Data Integrity Conceptual (*)

Correct 7. The logical model determines relationship optionality and cardinality

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True (*) False

Correct 8. The __________ model includes entities, attributes, UIDs, relationships as well as optionality and cardinality of these items.

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Hierarchical Physical Conceptual Logical (*)

Incorrect. Refer to Section 2 Lesson 6. 9. Capturing all required data is the only goal of entity relationship modeling.

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True False (*)

Correct

10. The conceptual model does all of the following except:

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Prevents mistakes and misunderstandings. Documents type of operating system to be used. (*) Takes into account regulations and laws goverining the industry being addressed. Describes the needs of the business.

Correct 11. A Unique Identifier has a NULL value for each instance of the entity for the lifetime of the instance. True or False

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True False (*)

Correct 12. The candidate UID that is chosen to identify an entity is called the Primary UID; other candidate UIDs are called Secondary UIDs.

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No, each Entity can only have one UID, the secondary one. No, it is not possible to have more than one UID for an Entity. Yes, this is the way UID's are named. (*) No, after UIDs are first sorted, the first one is called the Primary UID, the second is the Secondary UID, etc. Correct 13. One-to-Many relationships have cardinality of one or more in both directions. True or False?

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True False (*)

Correct 14. A relationship is transformed from logical to physical model using _________.

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Candidate Keys Composite Keys Foreign Keys (*) Secondary Keys

Correct 15. Matrix Diagrams are used to verify that all ____________ have been identified for an ERD.

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relationships (*) keys attributes entities

Incorrect. Refer to Section 2 Lesson 5.

1. People are not born with “numbers”, but a lot of systems assign student numbers, customer IDs, etc. A shoe has a color, a size, a style, but may not have a descriptive “number". So, to be able to uniquely and efficiently

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identify one instance of the entity SHOE, a/an ______________ UID can be created. Artificial (*) Structured Identification Unrealistic

Incorrect. Refer to Section 2 Lesson 4. 2. A Unique Identifier has a NULL value for each instance of the entity for the lifetime of the instance. True or False

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True False (*)

Correct 3. Which of the following entities most likely contains invalid attributes?

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Entity: Car. Attributes: Owner Occupation, Owner Salary, Speed (*) Entity: Home. Attributes: Number of Bedrooms, Owner, Address, Date Built Entity: Mother. Attributes: Name, Birthdate, Occupation, Number of Children Entity: Pet. Attributes: Name, Birthdate, Owner

Correct 4. When creating entities in a logical model you must follow these rules: (Choose Two)

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(Choose all correct answers) Exclude Attributes Include Attributes (*) Name them in Plural

Name them in Singular (*)

Correct 5. An entity may have which of the following?

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Experiences Instances (*) Tables None of the above

Correct

6. A __________ relationship is a relationship between an entity and itself.

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Recursive (*) One to one Hierarchical Mandatory

Correct 7. Which of the following are true about Cardinality? (Choose two)

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(Choose all correct answers) Cardinality tells "how many". (*) Cardinality specifies a counting number (like 1, 2, 3, 4 etc.) in a relationship. Cardinality specifies only singularity or plurality, but not a specific plural number. (*) Cardinality specifies whether something is required or not.

Correct 8. Which of the following is NOT a relationship type?

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One to One One to Many Many to Many Some to None (*)

Correct 9. The physical model shows all table structures. True or False.

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True (*) False

Correct 10. A conceptual model includes :

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Only Entities, Attributes and Relationships Only Entities, Attributes and Unique Identifiers Only Entities and Relationships (*) Entities, Attributes, Unique Identifiers and Relationships

Correct

11. Which of the following is not an advantage of a relational database?

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Efficiency

Less Redundancy Data Integrity One table with all the data. (*)

Incorrect. Refer to Section 2 Lesson 1. 12. Each column in a relation is called an entity. True or False?

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True False (*)

Correct 13. In an ERD diagram how is cardinality represented ? (Choose two)

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(Choose all correct answers) With a crow's foot (*) With a solid line With a dotted line With a single toe (*)

Incorrect. Refer to Section 2 Lesson 6. 14. ERDish is a language used to create database structures in SQL

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True False (*)

Correct 15. An ERD created using ERDish is a __________ representation of entities and their relationships to each other.

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hierarchical technical

textual graphical (*)

Correct...