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Oracle Execution Plan Techniques - Quiz

Each question is worth one point. Select the best answer or answers for each question.
1. What is true about bitmapped indexes on a column?
Please select the best answer.
  A. Bitmapped indexes are best when the column has a high number of distinct values.
  B. Bitmaps contain one entry for every row in the indexed table.
  C. Bitmapped indexes are intended to replace B-tree indexes in Oracle8.
  D. Bitmapped indexes are only suitable for data warehouse applications.

2. Which of the following are differences between a STAR query and a STAR TRANSFORMATION query?
Please select all the correct answers.
  A. The STAR techniques build intermediate results in memory, while the STAR TRANSFORMATION builds intermediate results in temporary segments.
  B. The STAR TRANSFORMATION runs faster than the STAR technique when few rows are returned from the bitmap queries.
  C. The STAR and STAR TRANSFORMATION techniques can only be used with the data warehouse option.
  D. The STAR technique requires a bitmapped index while the STAR TRANSFORMATION requires a concatenated index.

3. Which of the following are true about function-based indexes?
Please select all the correct answers.
  A. Any of the Oracle built-in functions may be used.
  B. You can create your own functions and include them in your index definition.
  C. You can use function-based indexes to build an index on a transformation of the column value.
  D. You can use built-in indexes as a replacement for bitmapped indexes.