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Rule-based Optimizer - Quiz

Each question is worth one point. Select the best answer or answers for each question.

1. What is true about the rule-based optimizer? (Choose all that apply)
Please select all the correct answers.
  A. The rule-based optimizer relies on statistics from the ANALYZE command.
  B. The rule-based optimizer chooses indexes based on their selectivity.
  C. The rule-based optimizer requires careful sequencing of items in the FROM and WHERE clauses.
  D. The rule-based optimizer is sometimes faster for complex multi-table equi-joins.

2. Which one of the following is a tuning step for rule-based queries?
Please select the best answer.
  A. Ensure that an index exists for the most selective item in the WHERE clause.
  B. Place the table that returns the largest number of rows last in the FROM clause.
  C. Place the Boolean conditions in order from most selective to least selective.
  D. Analyze the table to get the proper statistics for the optimizer.

3. Which one of the following is a technique for forcing the use of an index when the rule-based optimizer makes a poor choice? (Choose all that apply) Please select all the correct answers.
  A. Invalidate the index by placing a data type mismatch in the WHERE clause.
  B. Use an INDEX hint.
  C. Re-sequence the Booleans in the WHERE clause to place the desired index column last in the WHERE clause.
  D. Get index statistics with the ANALYZE INDEX command.