2014 Latest Oracle 1Z0-872 Exam Demo Free Download!

QUESTION 1
Assuming you want to add an index on the isofficial column, which of the following statements are true?
 clip_image002

A.    A SELECT query with WHERE lsOfficial=’T’ will perform much faster with the index because there aren’t
many rows with that value.
B.    A SELECT query with WHERE IsOfficial-`F’ will perform much faster with the index because there are
many rows with that value.
C.    A SELECT query with a WHERE condition on the IsOfficial column won’t perform much faster because
there are only few distinct values.
D.    Each UPDATE or INSERT statement will take longer because the additional index needs to be maintained.
E.    You cannot add an index on ENUM columns.

Answer: CD

Read more