Test your basic knowledge |

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. Query conditional allowing the selector to choose between more than one optional criteria.
$or
$size
$
$not

2. Used to represent both a null value and a nonexistent field.
maximum value
batch insert
null
$pullAll

3. Data structure used to store all other data in mongo databases.
string
document
null
db.<collection>.insert({document});

4. Not supported by the javascript shell and are converted to 64-bit floating point numbers.
db.<collection>.find([properties]);
show collections
mongo
64-Bit Integer

5. Does not contain query conditional used to select documents with the field that is not in the selector list of values.
use <database name>
$nin
key.index
32-Bit Integer

6. Greater than query conditional. ex: db.<col>.find({numVal: {$gt:3}});
$ne
$or
$gt
64-Bit Integer

7. Update a document in the collection.
db.<col>.update({selector},{document});
$ne
regular expression
$unset

8. Binary-encoded serialization of mongo documents.
string
32-Bit Integer
$size
BSON

9. 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 } }
$pop
Multi-updates
null
undefined

10. Operator allowing the partial specification of fields in an embedded document in an array.
$elemMatch
db.<collection>.findOne([properties]);
db.cloneDatabase(fromhost)
$or

11. Javascript code. Documents can contain code as values.
$nin
$or
mongo
code

12. command to start the mongo shell.
$pullAll
db.cloneDatabase(fromhost)
string
mongo

13. Contains query conditional used to check if a value contains the field value.
BSON
$gt
$in
key.index

14. Removes all occurrences of a value from a field. ex: { $pull : { field : _value } }
mongo
$gte
$pull
array

15. A document contained by a parent document. The embedded document is a value of a key in the parent document.
mongod
embedded document
use <database name>
string

16. Not equal query conditional. ex: db.<col>.find({numVal: {$ne:3}});
maximum value
$pushAll
use <database name>
$ne

17. Returns the size of a document after it is converted to BSON from the JSON-like original.
embedded document
db.<col>.help([commandName]);
$push
Object.bsonsize({document});

18. changes the database on which you are working.
use <database name>
string
$addToSet
boolean

19. 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.
$
$lt
db.copyDatabase(frmDBName, toDBName, [frmHostName], [user], [pwd]);
db.<collection>.insert({document});

20. Returns all the documents matching the optional properties.
Object.bsonsize({document});
db.<collection>.find([properties]);
boolean
db.<col>.help([commandName]);

21. Deletes documents from the collection based on the selector.
db.<col>.remove({selector});
maximum value
$ne
$push

22. Special keys passed in an update call to specify complex update operations - such as alter - adding - or removing keys - and even manipulating arrays and embedded documents.
$elemMatch
$in
date
Update Modifiers

23. Set or list of values.
Upsert
boolean
array
$push

24. Returns all the documents matching the optional properties.
db.commandHelp("commandName")
db.commandHelp("commandName")
db.<collection>.find([properties]);
$inc

25. Standard javascript regular expressions. These can be stored in documents
db.commandHelp("commandName")
$addToSet
regular expression
embedded document

26. 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.
$pullAll
mongod
db.myCollection.ensureIndex({keypattern},[{options}])
db.runCommand({fsync:1,lock:1,async:1})

27. Array specific conditional allowing matching on multiple elements within an array. The operation is non strict on the sequence of the values in the passed selector array.
$all
Multi-updates
$pull
db.myCollection.ensureIndex({keypattern},[{options}])

28. Command to get help docs on a specific command at the db level.
db.help([commandName]);
db.<collection>.find([properties]);
64-Bit Integer
use <database name>

29. Adds a document to a collection.
mongo
$lt
db.<collection>.insert({document});
regular expression

30. Adds a value to the array only if its not in the array already. Otherwise, if the field is not present, it sets the field to the array value. ex: { $addToSet : { a : { $each : [ 3 , 5 , 6 ] } } }
$lt
db.getLastError()
$where
$addToSet

31. Syntax used for selectors to be specific to a certain element position within an array.
$inc
key.index
use <database name>
$lte

32. Clone the current database (implied by 'db') from another host.
db.cloneDatabase(fromhost)
Object.bsonsize({document});
array
boolean

33. 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.
$lt
undefined
$elemMatch
$mod

34. Command to get help docs on a specific command at the collection level.
$pop
$mod
db.commandHelp("commandName")
db.<col>.help([commandName]);

35. Command to list commands and descriptions of those commands in the context of the database.
help
regular expression
$where
db.<collection>.insert({document});

36. changes the database on which you are working.
use <database name>
batch insert
key.index
help

37. String of arbitrary bytes.
Upsert
Cursor
binary data
db.runCommand({fsync:1,lock:1,async:1})

38. Renames a field from the one indicated to the new field name. ex: { $rename : { old_field_name : new_field_name } }
mongo
boolean
$rename
db.runCommand({fsync:1,lock:1,async:1})

39. Clone the current database (implied by 'db') from another host.
db.cloneDatabase(fromhost)
string
db.myCollection.ensureIndex({keypattern},[{options}])
$or

40. Greater than or equal query conditional. ex: db.<col>.find({numVal: {$gte:3}});
$gte
$all
$or
db.cloneDatabase(fromhost)

41. Stored as milliseconds since the epoch.
$gt
date
show collections
minimum value

42. Deletes documents from the collection based on the selector.
array
code
db.<col>.remove({selector});
key.index

43. command to start the mongodb process.
maximum value
help
mongod
db.getLastError()

44. In BSON - represents the smallest possible value.
$rename
db.<collection>.find([properties]);
minimum value
$not

45. 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
db.<col>.help([commandName]);
db.commandHelp("commandName")
help

46. Less than query conditional. ex: db.<col>.find({numVal: {$lt:3}});
$where
$gte
$lt
array

47. Not supported by the javascript shell and are converted to 64-bit floating point numbers.
use <database name>
minimum value
$lte
32-Bit Integer

48. command to start the mongodb process.
mongod
Multi-updates
maximum value
$rename

49. The standard number representation in the javascript shell.
64-bit floating point numbers
db.<collection>.insert({document});
$lte
embedded document

50. Operator used in the second argument of the find() call to specify which slice of an array to return for an array field.
$unset
$slice
key.index
db.cloneDatabase(fromhost)