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. Not equal query conditional. ex: db.<col>.find({numVal: {$ne:3}});
mongo
db.runCommand({fsync:1,lock:1,async:1})
$ne
mongod

2. changes the database on which you are working.
db.<collection>.find([properties]);
use <database name>
Cursor
$pullAll

3. Operator allowing the execution of arbitrary javascript as part of the selector.
$lt
db.<col>.remove({selector});
db.cloneDatabase(fromhost)
$where

4. Greater than or equal query conditional. ex: db.<col>.find({numVal: {$gte:3}});
string
$gte
mongo
Object.bsonsize({document});

5. Returns help information for a command.
db.<collection>.findOne([properties]);
binary data
db.commandHelp("commandName")
Cursor

6. Deletes documents from the collection based on the selector.
document
Object.bsonsize({document});
$mod
db.<col>.remove({selector});

7. Stored as milliseconds since the epoch.
code
$where
db.cloneDatabase(fromhost)
date

8. In BSON - represents the smallest possible value.
minimum value
$lte
$mod
$slice

9. ...
Object.bsonsize({document});
$addToSet
$rename
batch insert

10. Standard binary data type.
$gt
boolean
db.<col>.remove({selector});
$pushAll

11. Data structure used to store all other data in mongo databases.
document
db.<col>.remove({selector});
binary data
32-Bit Integer

12. Contains query conditional used to check if a value contains the field value.
$pullAll
db.commandHelp("commandName")
$size
$in

13. Returns all the documents matching the optional properties.
db.<col>.remove({selector});
Update Modifiers
db.runCommand({fsync:1,lock:1,async:1})
db.<collection>.find([properties]);

14. 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
$pullAll
$
$addToSet

15. Removes all occurrences of each value in the passed in array from the field. ex: { $pullAll : { field : value_array } }
db.commandHelp("commandName")
64-Bit Integer
$pullAll
db.<col>.update({selector},{document});

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

17. Adds a document to a collection.
db.<collection>.insert({document});
embedded document
db.<col>.remove({selector});
string

18. Standard javascript regular expressions. These can be stored in documents
32-Bit Integer
$all
regular expression
$lt

19. Does not contain query conditional used to select documents with the field that is not in the selector list of values.
boolean
$nin
$push
$rename

20. changes the database on which you are working.
string
$lt
db.<collection>.find([properties]);
use <database name>

21. Binary-encoded serialization of mongo documents.
BSON
binary data
64-Bit Integer
db.<col>.help([commandName]);

22. Set or list of values.
$not
array
Multi-updates
$pop

23. Positional operator that holds the position of the first matched array item in the query. Used to find an array member and then manipulate it. ex: {$inc:{'comments.$.votes':1}} where comments looks like: "comments" : [ { "by" : "joe", "votes" : 3 },
64-bit floating point numbers
$slice
$
embedded document

24. Used to represent both a null value and a nonexistent field.
mongod
$all
null
db.<collection>.find([properties]);

25. Update modifier that set the value of a key and if the key does not exist, it will create the key. ex: db.<col>.update({selector},{"$set":{"someKey":"someValue"}});
$unset
$mod
$set
mongo

26. Returns all the documents matching the optional properties.
64-bit floating point numbers
64-Bit Integer
Update Modifiers
db.<collection>.find([properties]);

27. Not supported by the javascript shell and are converted to 64-bit floating point numbers.
$pushAll
db.<collection>.insert({document});
64-Bit Integer
document

28. set of UTF-8 characters.
Multi-updates
$pull
use <database name>
string

29. 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.
$rename
$slice
$unset
db.copyDatabase(frmDBName, toDBName, [frmHostName], [user], [pwd]);

30. 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 } }
use <database name>
db.help([commandName]);
$pop
mongod

31. Meta query conditional used to negate the selector.
$not
embedded document
db.<collection>.findOne([properties]);
$push

32. Deletes documents from the collection based on the selector.
show collections
db.<col>.remove({selector});
$set
$unset

33. Lists all the collections in the database in use.
show collections
use <database name>
Cursor
$gt

34. Appends each value in the value_array to the field - if field is an existing array. Otherwise - it sets the field to the array value_array - if field is not present ex: { $pushAll : { field : value_array } }
$pushAll
$push
db.copyDatabase(frmDBName, toDBName, [frmHostName], [user], [pwd]);
mongod

35. Command to list commands and descriptions of those commands in the context of the database.
db.<collection>.insert({document});
help
db.<col>.update({selector},{document});
db.<collection>.find([properties]);

36. Unique 12-byte ID for documents.
$ne
object id
BSON
date

37. Greater than query conditional. ex: db.<col>.find({numVal: {$gt:3}});
$pop
$gt
$lte
db.<col>.help([commandName]);

38. Adds a document to a collection.
$pushAll
db.<collection>.insert({document});
$nin
$where

39. Returns help information for a command.
show collections
$all
db.commandHelp("commandName")
db.<col>.remove({selector});

40. 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.
show collections
db.cloneDatabase(fromhost)
$in
Upsert

41. command to start the mongodb process.
mongod
$gte
binary data
use <database name>

42. The standard number representation in the javascript shell.
$in
$where
$size
64-bit floating point numbers

43. Operator allowing the partial specification of fields in an embedded document in an array.
db.<collection>.find([properties]);
embedded document
$slice
$elemMatch

44. Updates all matching documents, not just the first, that match the selector.
$pushAll
$unset
Multi-updates
db.<col>.remove({selector});

45. Returns one document matching the optional properties.
Upsert
64-Bit Integer
undefined
db.<collection>.findOne([properties]);

46. Syntax used for selectors to be specific to a certain element position within an array.
key.index
Update Modifiers
$push
$pullAll

47. In BSON - represents the largest possible value.
binary data
db.<col>.remove({selector});
maximum value
db.<col>.remove({selector});

48. command to start the mongo shell.
mongo
db.<collection>.find([properties]);
$push
array

49. A document contained by a parent document. The embedded document is a value of a key in the parent document.
embedded document
db.<collection>.insert({document});
db.<collection>.find([properties]);
$size

50. 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.
$ne
$pull
db.<collection>.findOne([properties]);
$all