1. 1. MongoDB
2. 2. Overview
3. 1. 2.1. MongoDB ("humongous") (= huge; enormous.)
   2. 2.2. 5 types of NoSQL databases
   3. 2.3. Languages
   4. 2.4. Documentation
   5. 2.5. Features
   6. 2.6. Limitations
   7. 2.7. Performance
   8. 2.8. Auto-sharding
   9. 2.9. Sharding
   10. 2.10. Picking a Shard Key
   11. 2.11. Replica set - high availability and data duability
   12. 2.12. Write concern
   13. 2.13. Storage Engines
   14. 2.14. MongoDB Data format
   15. 2.15. Driver Responsibility
4. 3. First steps
5. 1. 3.1. SQL to MongoDB terms
   2. 3.2. Embedded documents
   3. 3.3. GUI client for MongoDB
   4. 3.4. Atlas hosted environment
   5. 3.5. Command line tools
   6. 3.6. MongoDB on the command line
   7. 3.7. insert
   8. 3.8. insert more
   9. 3.9. Pretty printing in the MongoDB shell
   10. 3.10. find
   11. 3.11. update a document
   12. 3.12. Update modifiers for fields
   13. 3.13. update - add values using $set
   14. 3.14. update - add array using $set
   15. 3.15. remove value from document
   16. 3.16. transaction in a document
   17. 3.17. push
   18. 3.18. Update modifiers for arrays
   19. 3.19. Update array element
   20. 3.20. Remove array element
   21. 3.21. _id is unique in a collection
   22. 3.22. update and save
   23. 3.23. save()
   24. 3.24. Remove (delete) document
   25. 3.25. Count documents
   26. 3.26. Find deeply
   27. 3.27. sort()
   28. 3.28. push
   29. 3.29. Update modifiers
   30. 3.30. Conditional Operators
   31. 3.31. Indexes
   32. 3.32. Creat Indexes
   33. 3.33. Unique Index
   34. 3.34. Sparse index
   35. 3.35. Index embedded document (or subkey)
   36. 3.36. Insert complex data structure
   37. 3.37. Display complex data structure
   38. 3.38. Rename embedded document
   39. 3.39. Remove ($unset) embedded document
   40. 3.40. Change element of array
   41. 3.41. Add embedded document
   42. 3.42. Remove elements of an array by value
   43. 3.43. Remove elements of an array by index (trick)
   44. 3.44. Append one element to an array
   45. 3.45. Append multiple elements to an array
   46. 3.46. Insert multiple elements in an array
   47. 3.47. Drop collection
   48. 3.48. Drop database
   49. 3.49. MongoDB shell tools
   50. 3.50. Resources
   51. 3.51. Projection
6. 4. Aggregation
7. 1. 4.1. Aggregation framework
   2. 4.2. A Processing Pipeline
   3. 4.3. Pipeline Operators
   4. 4.4. Example: Insert data
   5. 4.5. Show data
   6. 4.6. Group by name and sum - $sum
   7. 4.7. Group by name and caluclate average $avg
   8. 4.8. Group by name $max, $min
   9. 4.9. Group by name and count
   10. 4.10. All the elements - sum
   11. 4.11. All the elements - sum
   12. 4.12. $match (filter)
   13. 4.13. $match (filter) and the total
   14. 4.14. $match with $gt
   15. 4.15. $group with $push
   16. 4.16. New data set
   17. 4.17. New data set
   18. 4.18. $unwind
   19. 4.19. $unwind and $group
   20. 4.20. $unwind and $group and $sort
   21. 4.21. $match
   22. 4.22. $match and $unwind and $group
8. 5. Mailbox analyzing
9. 1. 5.1. Email messages
   2. 5.2. find
   3. 5.3. Find by date
   4. 5.4. Messages that have CC field
   5. 5.5. Large messages
   6. 5.6. List the 10 biggest messages
   7. 5.7. The total size of the messages - aggregate
   8. 5.8. The total size of the messages - mapReduce
10. 6. MongoDB with Perl
11. 1. 6.1. Simple
    2. 6.2. Update
    3. 6.3. Unique
    4. 6.4. Increment
    5. 6.5. Phonebook
12. 7. MongoDB with Python
13. 1. 7.1. Simple