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Question
Assuming the "Quantity" column of an ORDER table contains integer data, what does COUNT(Quantity) compute?A) The number of rows in the ORDER table
B) The number of non-zero values in the Quantity column
C) The number of distinct values in the Quantity column
D) The number of non-null values in the Quantity column
Answer
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Related questions
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Suppose you have created a data model for an airline based on a variety of forms, reports, user interviews, data sources, etc. Your client comes forward with a new desired report that includes passenger weights and a relationship between passengers and employees, neither of which is in your E-R diagram. You should ________.
A) create a new, separate E-R diagram with just the new information
B) add the relationship and the weight attribute to the existing data model
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ID-dependent entities are a common type of weak entity.
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Q:
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Q:
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B) limits the number of rows retrieved from a table
C) limits the number of tables retrieved from a database
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A) relationships
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C) updatability
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Q:
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