51. | When mapping a ternary relationship with an associative entity into a relation which of the following is true? |
Discuss |
Answer: (d).Four relations are created.
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52. | When mapping a supertype/subtype relationship which of the following is true? |
Discuss |
Answer: (a).The supertype primary key is assigned to each subtype.
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53. | If no multivalued attributes exist in a relation, then the relation is in what normal form? |
Discuss |
Answer: (a).First normal form
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54. | If no multivalued attributes exist and no partial dependencies exist in a relation, then the relation is in what normal form? |
Discuss |
Answer: (b).Second normal form
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55. | A transitive dependency is which of the following? |
Discuss |
Answer: (b).A functional dependency between two or more nonkey attributes.
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56. | What is the best data type definition for Oracle when a field is alphanumeric and has a fixed length? |
Discuss |
Answer: (b).CHAR
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57. | If a denormalization situation exists with a many-to-many or associative binary relationship, which of the following is true? |
Discuss |
Answer: (b).All fields are stored in two relations.
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58. | Which of the following is an advantage of partitioning? |
Discuss |
Answer: (d).Security
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59. | Sequential retrieval on a primary key for sequential file storage has which of the following features? |
Discuss |
Answer: (a).Very fast
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60. | A rule of thumb for choosing indexes for a relational database includes which of the following? |
Discuss |
Answer: (d).Be careful indexing attributes that have null values.
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