Oracle Academy Mid Term Sem 1 | Oracle Database | Databases

October 20, 2017 | Author: Anonymous | Category: Oracle
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A business rule such as "We only ship goods after customers have completely paid any outstanding balances on their accou...

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Oracle Academy - Mid Term Semester 1 Raspunsurile CORECTE sunt cele care au (*) Sectiunea 1

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1. Users with detailed business knowledge can provide input i nput to the Database Development Process? True or False? - True (*) - False

2. Consider your school library. It will have a database with transaction details of which student borrows which books. Is a record of one student borrowing one book Data or Information? - Data (*) - Information - Both - Neither 3. Oracle Database Software provides which of the following functionality? (Choose t wo) - Graphical User Interface (*) - Internet Browser - Server (*) - Operating System 4. The main subject areas taught by the Oracle Academy are: - Computer Repairs - Database performance tuning. - Data Modeling, SQL and PL/SQL (*) - Systems programming and computer architecture

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5. Attributes have Instances. True or False? - True - False (*)

6. Data modelling is performed for the following reasons: (Choose Two) - The ERD's becomes a blueprint for designing the t he actual system. (*) - It helps discussions and reviews. (*) - We do not need datamodels, we can just start coding right away. - We just draw the ERD's to please the users, once they are finished we never look at them again. They serve no purpose in the real world. 7. All of the following would be instances of the entity ANIMAL SPECIES except which? - Dog - Bird - Elephant - Leaf (*)

8. Volatile entities have special requirements and need special attention when you are doing data modelling. True or False?

- True (*) - False 9. The entity/relationship model is created before the physical database design mode l? True or False? - True (*) - False 10. An entity can have many Unique Identifiers. True or False? - True (*) - False

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11. All of the following are examples of ENTITY: Instance except two. Select the answers that are ENTITY: Instance. (Choose Two) - TRANSPORTATION METHOD: Car (*) - ANIMAL: Dog (*) - MEAT PRODUCT: Lettuce - BODY PART: Larry Ellison

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12. When reading an ERD including Relationships you are said to be speaking: - Relationship-ish - Gibberish - ERDish (*) - Entity-ish

13. Relationships represents something of significance to the business. True or False? - True (*) - False 14. Relationship Degree/Cardinality is important. True or False? - True (*) - False 15. Matrix Diagrams are used to verify an ERD. True or False? - True (*) - False

16. Which symbol is used to show that a particular attribute is mandatory? - * (*) -o -# -&

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17. Why is it important to identify and document structural rules? - Ensures we know what data to store and how that data works together. (*) - Ensures nothing. There are no benefits to be gained from documenting your Structural Business Rules. We need to concentrate on the Procedural Business Rules only. - Ensures we know what Information to store and how that Information works together. - All of the Above.

18. "Only teachers may supervise exams" is an example of which of the following? - A procedural business rule (*) - An attribute that should be stored on the PERSON entity - A structural business rule - An attribute that is not be inherited from the PERSON supertype and is unique t o the TEACHER subtype

19. Business rules are important to data modelers. True or False? -True (*) -False

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20. A business rule such as "We only ship goods after customers have completely paid any outstanding balances on their account" is best enforced by: - Making the payment attribute null. - Making the payment attribute optional. - We need to trust our customers, and we know they will pay some da y. - Hiring a programmer to create additional programming code to verify no goods are shipped until the account has been settled in full. (*) 21. All instances of the supertype must be an instance of one of the subtypes. True or False? - True (*) - False 22. All instances of a subtype may be an instance of the supertype but does not have to. True or False? - True - False (*) 23. When creating entities you must follow these rules: (Choose Two) - Name them in Plural - Name them in Singular (*) - Exclude Attributes - Include Attributes (*) 24. The "Other" subtype is mandatory. True or False? - True - False (*)

25. Which of the following is true about subtypes? - One instance may belong to two subtypes of the same supertype. - Subtypes must be mutually exclusive. (*) - Subtypes must not be mutually exclusive. - Subtype entities may not have relationships to the other subtype entities, only the supertype itself.

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26. Intersection Entities often have the relationships participating in the UID, so the relationships are often barred. True or False? - True (*) - False 27. If two entities have two relationships between them, these relationships can be ei ther  _____________ or _____________ ? - Redundant or Required (*)

- Replicated or Required - Resourced and Really Good - Redundant and Replicated 28. Relationships can be Redundant. True or False? - True (*) - False 29. How do you include a relationship as part of the UID for an entity? - By barring the relationship in question (*) - By reporting it in an external document - By including the UID from the parent entity as an attribute in t he entity - You cannot model that.

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30. Many to many relationships must be left in the Model. It is important to have them documented as M-M. True or False? - True - False (*)

31. If a relationship can NOT be moved between instances of the entities it connects, it is said to be: - Mandatory - Optional - Transferrable - Non-Transferrable (*) 32. As a database designer you do not need to worry about where in the datamodel you store a particular attribute, as long as you get it onto the ERD your job is done. Tr ue or False? - True - False (*) 33. Any Non-UID must be dependant on the entire UID. True or False? - True (*) - False

34. Normalizing an Entity to 1st Normal Form is done by removing repeated or redundant attributes. True or False? - True (*) - False 35. The is no limit to how may UID's an entity can have. True or False? - True (*) - False

36. A relationship can be both Recursive and Hierachal at the same time. True or False? - True - False (*) 37. No parts of an UID are mandatory. True or False? - True - False (*)

38. Primary UIDs are: - Something that each Entity should have, but is not mandatory - Useful as an alternative means of identifying instances of an entity, independent of their datatype

- Mandatory in data modeling (*) - Always comprised of numbers 39. Consider the entity ADDRESS with the attributes: ADDRESS: # House Number * Street * Town * City * Year of Build o City Population

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This entity is NOT in 3rd Normal Form ("no non-UID attribute can be dependent on another nonUID attribute). True or False? - True (*) - False 40. Arcs are used to visually represent _________ between two or more relationships i n an ERD. - Sameness - Differences - Exclusivity (*) - Inheritance 41. Which of the following is NOT a relationship type? - Some to None (*) - One to One - One to Many - Many to Many

42. Modeling historical data can produce a unique identifier that always excludes dates. True or False? - True - False (*) 43. Consultants often use their experience in ensuring projects stay on track and delivers within the timescales set out for the project. True or False? - True (*) - False 44. Your apperance at a presentation is important. You need to look smart and presentable. True or False? - True (*) - False 45. There is only one way to model time in a Data Model. True or False? - True - False (*)

46. Which of the following would be a logical constraint when modeling time for a City entity? - People are born in the city and people die in the city. - Cites may change their name and/or which country they are placed in, if the borders of a country change. (*) - Cites may change their name and/or which country they are placed in, if the borders of a country change. (*) - If you are doing a system for any French City, you would need security clearance

- You need a constant record of cities because they are still cities, even i f leadership changes over time, e.g. they get a new Mayor 47. Modeling historical data is Optional. True or False? - True (*) - False 48. When you add the concept of time to your data model, your model becomes more complex. True or False? - True (*) - False

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49. You are doing a data model for a computer sales company, where the price of postage is dependent on what day of the week goods are shipped. So shipping is more expensive if the customer wants a delivery to take place on a Saturday or Sunday. What would be the best way to model this? - Use a Delivery Day entity, which holds prices against week days, and ensure the we also have an attribute for the Requested Delivery Day in the Order Entity. (*) - Email current price to all employees whenever the prices change. - Update the prices in the system, print out the current prices when they change and pin them on the company noticeboard. - Allow them to enter whatever ever delivery charge they want. 50. Which of the following is a logical constraint that could result from considering how time impacts an example of data storage? - An ASSIGNMENT may only refer to an EMPLOYEE with a valid employee record at the Start Date of the ASSIGNMENT. (*) - EMPLOYEE periods can overlap causing the database to crash. - End Date must be before the Start Date. - Dates must be stored with Time.

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