Question 3

Which of the following statements is/are true?

Answer:
  • MongoDB indexes are markov trees. - No as MongoDB indexes are designed using B-trees.
  • By default, all MongoDB user-created collections have an _id index. - Yes
  • Background index builds block all reads and writes to the database that holds the collection being indexed - No,  as foreground index builds block all reads and writes to the database that holds the collection being indexed. Background index builds don't have this limitation, but are generally slower than foreground index builds.
  • It's common practice to co-locate your mongos on the same machine as your application to reduce latency - Yes
  • Collations can be used to create case insensitive indexes - Yes





Comments

  1. Azure DevOps14 September 2018 at 23:57

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  2. Shanmugam28 April 2021 at 05:57

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  3. Deva6 May 2022 at 02:57

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