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Question
If the SQL statementSELECT C1, C2, C3
FROM T4
WHERE C2 = 'Smith';
is frequently executed, which column(s) should be considered for indexing based only on the statement itself?
A) C1 only
B) C2 only
C) C3 only
D) C1 and C2
Answer
This answer is hidden. It contains 1 characters.
Related questions
Q:
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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Q:
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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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Q:
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C) updatability
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Q:
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