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Mongo Db

Subject : it-skills

Instructions:

Answer 50 questions in 15 minutes.
If you are not ready to take this test, you can study here.
Match each statement with the correct term.
Don't refresh. All questions and answers are randomly picked and ordered every time you load a test.

This is a study tool. The 3 wrong answers for each question are randomly chosen from answers to other questions. So, you might find at times the answers obvious, but you will see it re-enforces your understanding as you take the test each time.

1. Update call that inserts a new document if no update match is found. Allows the same code to be used for inserts as well as updates.
$nin
db.copyDatabase(frmDBName, toDBName, [frmHostName], [user], [pwd]);
$all
Upsert

2. Meta query conditional generating a modulus with the selector operand. Checks to see if the field value when divided by one value has the remainder of the second value.
$mod
db.<collection>.find([properties]);
32-Bit Integer
date

3. Returns help information for a command.
$elemMatch
db.commandHelp("commandName")
db.<col>.help([commandName]);
undefined

4. Removes all occurrences of each value in the passed in array from the field. ex: { $pullAll : { field : value_array } }
$addToSet
db.copyDatabase(frmDBName, toDBName, [frmHostName], [user], [pwd]);
$pullAll
document

5. Returns the size of a document after it is converted to BSON from the JSON-like original.
$ne
32-Bit Integer
Cursor
Object.bsonsize({document});

6. Does not contain query conditional used to select documents with the field that is not in the selector list of values.
db.<col>.remove({selector});
minimum value
mongo
$nin

7. Not equal query conditional. ex: db.<col>.find({numVal: {$ne:3}});
$ne
$where
$mod
$push

8. Array specific conditional used to select based on the length or set-size of an array field value.
object id
db.<collection>.find([properties]);
boolean
$size

9. The standard number representation in the javascript shell.
binary data
$pop
64-bit floating point numbers
array

10. In BSON - represents the smallest possible value.
minimum value
db.<col>.remove({selector});
$all
db.<collection>.findOne([properties]);

11. Deletes documents from the collection based on the selector.
db.<col>.remove({selector});
BSON
show collections
$lte

12. Javascript code. Documents can contain code as values.
BSON
$all
$unset
code

13. Flushes all pending writes to data files. The lock option allows one to safely snapshot the database's data files. The async option returns focus to the console immediately while the task runs in the background.
$unset
db.runCommand({fsync:1,lock:1,async:1})
$gt
db.<col>.remove({selector});

14. String of arbitrary bytes.
$pop
db.myCollection.ensureIndex({keypattern},[{options}])
db.copyDatabase(frmDBName, toDBName, [frmHostName], [user], [pwd]);
binary data

15. Less than or equal query conditional. ex: db.<col>.find({numVal: {$lte:3}});
$lte
$in
$nin
$rename

16. command to start the mongo shell.
mongo
db.myCollection.ensureIndex({keypattern},[{options}])
db.<collection>.insert({document});
code

17. Greater than query conditional. ex: db.<col>.find({numVal: {$gt:3}});
$gt
$nin
$
$ne

18. set of UTF-8 characters.
string
64-bit floating point numbers
$lt
undefined

19. Updates all matching documents, not just the first, that match the selector.
Multi-updates
db.<col>.remove({selector});
date
boolean

20. Less than query conditional. ex: db.<col>.find({numVal: {$lt:3}});
$lt
maximum value
document
$slice

21. Removes all occurrences of a value from a field. ex: { $pull : { field : _value } }
$pull
$not
BSON
$where

22. Query conditional allowing the selector to choose between more than one optional criteria.
$in
$or
mongod
object id

23. Returns information about the last operation. Not necessarily error data - the return can contain things like number of records updated.
db.<col>.help([commandName]);
Cursor
$elemMatch
db.getLastError()

24. Clone the current database (implied by 'db') from another host.
$mod
db.<collection>.insert({document});
$in
db.cloneDatabase(fromhost)

25. Command to get help docs on a specific command at the collection level.
db.<col>.help([commandName]);
object id
$gt
db.<collection>.find([properties]);

26. Standard binary data type.
code
64-Bit Integer
boolean
mongo

27. Binary-encoded serialization of mongo documents.
BSON
batch insert
Multi-updates
db.help([commandName]);

28. Adds a document to a collection.
db.<col>.help([commandName]);
regular expression
db.<collection>.insert({document});
db.copyDatabase(frmDBName, toDBName, [frmHostName], [user], [pwd]);

29. Greater than or equal query conditional. ex: db.<col>.find({numVal: {$gte:3}});
Cursor
db.<collection>.find([properties]);
$gte
null

30. Set or list of values.
$or
db.<col>.help([commandName]);
array
64-bit floating point numbers

31. command to start the mongodb process.
mongod
key.index
Multi-updates
db.cloneDatabase(fromhost)

32. Clone the current database (implied by 'db') from another host.
$pullAll
date
db.cloneDatabase(fromhost)
Upsert

33. Deletes a given field. ex: { $unset : { field : 1} }
BSON
$unset
Update Modifiers
db.<collection>.find([properties]);

34. Command to list commands and descriptions of those commands in the context of the database.
BSON
db.<col>.update({selector},{document});
help
$ne

35. changes the database on which you are working.
$pop
db.<col>.update({selector},{document});
string
use <database name>

36. Deletes documents from the collection based on the selector.
$addToSet
db.<col>.remove({selector});
$nin
document

37. Copies an entire database from one name on one server to another name on another server. Omit frmHostName to copy from one name to another on the same server.
$pull
$
db.copyDatabase(frmDBName, toDBName, [frmHostName], [user], [pwd]);
$gt

38. Appends a value to field - if the field is an existing array. Otherwise it sets the field to the array [value] if field is not present. ex: { $push : { field : value } }
$push
regular expression
64-bit floating point numbers
$gt

39. Update modifier used to increment a value. ex: {"$inc":{"counter":2}}
mongod
$inc
db.<collection>.findOne([properties]);
mongod

40. The local variable representation of a query. Uniquely - the cursor does not hold the results but instead access to the results.
Upsert
Cursor
db.<col>.help([commandName]);
$all

41. Unique 12-byte ID for documents.
object id
db.commandHelp("commandName")
$elemMatch
db.<collection>.insert({document});

42. Creates an index on property(s). Options can describe the type of sorting, uniqueness, etc.
$in
Upsert
db.myCollection.ensureIndex({keypattern},[{options}])
db.<collection>.find([properties]);

43. Command to get help docs on a specific command at the db level.
document
db.copyDatabase(frmDBName, toDBName, [frmHostName], [user], [pwd]);
db.help([commandName]);
$in

44. Standard javascript regular expressions. These can be stored in documents
db.<collection>.find([properties]);
use <database name>
$inc
regular expression

45. Used to describe a variable as not having been initialized.
db.getLastError()
undefined
64-Bit Integer
db.<collection>.insert({document});

46. Syntax used for selectors to be specific to a certain element position within an array.
$addToSet
key.index
$all
regular expression

47. Returns all the documents matching the optional properties.
Object.bsonsize({document});
batch insert
use <database name>
db.<collection>.find([properties]);

48. Removes an element from an array based on the value of the field option being 1 or -1 for last or first element respectively. ex: { $pop : { field : -1 } }
$rename
date
help
$pop

49. command to start the mongodb process.
$pullAll
db.<collection>.insert({document});
mongod
$unset

50. Operator used in the second argument of the find() call to specify which slice of an array to return for an array field.
$size
$slice
$inc
$push