Insert Documents in mongodb.

Overview of chapter 2 commands in mongodb.

collection.starts() and collection.drop() command in mongodb.

db.currentop() and db.killop() command in mongodb

db.serverstatus() command in mongodb.

db.ismaster() command in mongodb.

db.run command in mongodb.

Command operators in mongodb.

Bulk wire operators in mongodb.

Wire protocol in mongodb.

Lecture Notes At around 2:09, Dwight specifies the 'basic building blocks' of the wire protocol, and includes Commands in that. Just to clarify Dwight's intention, Commands are not built into the wire protocol as basic building blocks, even though they are a basic conceptual building block.

Upserts in mongodb.

Lecture Notes When this video was originally recorded, for MongoDB 2.6, the format was: > db.collection.update( query_document , update_document , [ upsert_boolean , [ multi_boolean ] ] ) This is no longer the recommended format. We now recommend: > db.collection.update( query_document, update_document, options_document ) where options_document contains key:value pairs such as: multi : true/false, upsert : true/false, writeConcern: document

update operators in mongodb,

Delete doccument in mongodb.

Partial update in mongodb.

Update in mongodb doccuments.

Adminstartive command in mongodb

welcome to chapter-2

Quiz and Homework of MongoDB

Quiz: Concepts

Q.>What were the big differences in hardware over the last few decades that MongoDB attempted to address?

1.Parallelism of cores

2.Parallelism of servers

3.Quantum computers

4.Faster clock speeds

5.More memory

Ans.

1.Parallelism of cores

2.Parallelism of servers

Quiz: Scaling

Q: When scaling out horizontally (adding more servers to contain your data), what are problems that arise as you go from, say, 1 commodity server to a few dozen?

1. The original server, if incorporated into the cluster, is more likely to fail in a given unit of time than if it had been left as a single server.

2. The servers must communicate with one another eating up network bandwidth

3. The need for redundancy increases as the likelihood of some failure in the system per unit of time increases.

4. Hardware cost per server is likely to increase.

Ans

2. The servers must communicate with one another eating up network bandwidth

3. The need for redundancy increases as the likelihood of some failure in the system per unit of time increases.

Quiz: SQL and Complex Transactions

Q: What causes significant problems for SQL when you attempt to scale horizontally (to multiple servers)?

1. Joins

2. Queries

3. Transactions

4. Inserts

5. Indexes

Ans.

1. Joins

3. Transactions

Quiz: Documents Overview

Q.> What are some advantages of representing our data using a JSON-like format?

1. JSON presents a flexible and concise framework for specifying queries as well as storing records.

2. JSON syntax is similar to that of common data structures used in many programming languages and is, therefore, familiar to developers.

3. JSON is language independent.

4. JSON is optimized for use with JavaScript.

Ans.

1. JSON presents a flexible and concise framework for specifying queries as well as storing records.

2. JSON syntax is similar to that of common data structures used in many programming languages and is, therefore, familiar to developers.

3. JSON is language independent.

Quiz: JSON Syntax

Quiz: JSON Types

Q.> How many data types are there in JSON?

a. 1 (just strings)

b. 2

c. 4

d. 6

Ans

d. 6

Q.> What is the corresponding JSON for the following XML document?

<person>

  <name>John</name>

  <age>25</age>

  <address>

    <city>New York</city>

    <postalCode>10021</postalCode>

  </address>

  <phones>

    <phone type="home">212-555-1234</phone>

    <phone type="mobile">646-555-1234</phone>

  </phones>

</person>

Ans

{

"name" : "John",

"age" : 25,

"address" : { "city" : "New York", "postalCode" : "10021" },

"phones" : [ {"phone":"212-555-1234", "type" : "home"}, {"phone":"646-555-1234", "type" : "mobile"} ]

 }

Quiz: JSON Syntax 2

Q.> For the following XML, Is the corresponding JSON example legal json?

<things>

  <hat>one</hat>

  <coat>z</coat>

  <hat>two</hat>

</things>

{

  "hat" : "one",

  "coat" : "z",

  "hat" : "two"

}

1. Yes

2. No

3. Maybe

Ans

3. Maybe

Quiz: Binary JSON

Q.> Why do we represent our data as BSON rather than JSON in the system?

1. Fast machine scanability.
2. Human readability.
3. Stronger typing (and more types) than JSON

 Ans.

1. Fast machine scanability.

3. Stronger typing (and more types) than JSON

Quiz: BSON and applications

Q.> For a typical client (a python client, for example) that is receiving the results of a query in BSON, would we convert from BSON to JSON to the client's native data structures (for example, nested dictionaries and lists in Python), or would we convert from BSON straight to those native data structures?

  

1.  BSON -> Native data structures
2. BSON -> JSON -> Native data structures

 Ans.

1. BSON -> Native data structures

Quiz: Dynamic Schema

Q.> True or False: MongoDB is schemaless because a schema isn't very important in MongoDB

1. True
2. False

 Ans. 

2. False

Quiz: What is the MongoDB shell?

Q: By default, which database does the mongo shell connect to?

1. test
2. localhost
3. mongo
4. help
5. default

 Ans

1. test

Quiz: Mongoimport

The mongoimport utility can import what types of data?

1. JSON
2. CSV
3. BSON
4. TSV
5. XML

 Ans.

1. JSON
2. CSV
3. BSON
4. TSV

Quiz: Cursors Introduction

In order to query a collection in the mongo shell, we can type which of the following?

1. db.collection.find()
2. db.find()
3. db.collection.get()
4. db.collection.select(*)
5. db.collection.get(true)

 Ans.

5. db.collection.find()

None: Query Language: Basic Concepts

Q.> You have a collection where every document has the same fields, and you want to look at the value of the “_id”, "name", and “email” fields in order to see their format. Furthermore, you want to eliminate all other fields from the query results. What query might you write?

1. db.collection.find({ name : 1, email: 1 }, {} )
2. db.collection.find( { } , { name: 1 , email: 1 } )
3. db.collection.find( { name: 1 } , { email : 1 } )
4. db.collection.find( {name: 1 , email: 1 } )

 Ans.

2. db.collection.find( { } , { name: 1 , email: 1 } )

Quiz: Query Language: Projection

Q.> You want to query the “people” collection, you want the results of the query to include only documents where age is 50, and you want to look at all fields except “email”. What query should you write?

1. db.people.find( { email : 0, age : 50 } , { } )
2. db.people.find( { email : 0 }, { age : 50 } )
3. db.people.find( { age : 50 } , {email: 0 } )
4. db.people.find( { } , { email : 0 , age : 50 } )
5. db.people.find( { age : 50 }, {email : 1} )

 Ans.

3. db.people.find( { age : 50 } , {email: 0 } )

Quiz: Query Language: Advantages of a Dynamic Schema

Q.> If you want to add a new key: value pair to the documents in the “shapes” collection, what methods could you use?

1. db.shapes.alterCollection()
2. db.shapes.update()
3. db.shapes.resizeObject()
4. db.shapes.find()
5. db.shapes.save()

 Ans.

2. db.shapes.update()

4. db.shapes.save()

Quiz: Sorting

Q.> If you want to run a query on the collection, “books,” and sort ASCIIbetically by title on the query, which of the following will work?

1. db.books.find( { } , { sort : { title : 1 } } )
2. db.books.find( { } , { title : "$sort" } )
3. db.books.find( { } ).sort( { title : -1 } )
4. db.books.sort( { title : 1 } ).find( { } )
5. db.books.find().sort( { title : 1 } )

Ans.

5. db.books.find().sort( { title : 1 } )

Quiz: Query Language: Cursors

Q. > Recall the documents in the scores collection:

{

                "_id" : ObjectId("50844162cb4cf4564b4694f8"),

                "student" : 0,

                "type" : "exam",

                "score" : 75

}

Write a query that retrieves documents of type "exam", sorted by score in descending order, skipping the first 50 and showing only the next 20.

Ans 

db.scores.find( { type : "exam" } ).sort( { score : -1 } ).skip( 50 ).limit( 20 )

Homework: Homework 1.1

Download and install MongoDB from www.mongodb.org. Then run the database as a single server instance on your PC (that is, run the mongod binary). Then, run the administrative shell.

From the shell prompt type

 db.isMaster().maxBsonObjectSize

at the ">" prompt.

What do you get as a result?

Ans.

16777216

Homework: Homework 1.2

Download the handout. Take a look at its content.

Now, import its contents into MongoDB, into a database called "pcat" and a collection called "products". Use the mongoimport utility to do this.

When done, run this query in the mongo shell:

db.products.find( { type : "case" } ).count()

What's the result?

 Ans.

 3

Homework: Homework 1.3

At this point you should have pcat.products loaded from the previous step. You can confirm this by running in the shell:

db.products.find()

// or:

db.products.count()

// should print out "11"

Now, what query would you run to get all the products where brand equals the string “ACME”?

Ans.

db.products.find({"brand": "ACME"})

Homework: Homework 1.4

How would you print out, in the shell, just the value in the "name" field, for all the product documents in the collection, without extraneous characters or braces, sorted alphabetically, ascending? (Check all that would apply.)

1. var c = db.products.find( { } ).sort( { name : -1 } ); while( c.hasNext() ) { print( c.next().name); }

2. var c = db.products.find( { }, { name : 1, _id : 0 } ).sort( { name : 1 } ); while( c.hasNext() ) { print( c.next().name); }

3. var c = db.products.find( { } ).sort( { name : 1 } ); c.forEach( function( doc ) { print( doc.name ) } );

4. db.products.find( { }, { name : 1, _id : 0 } ).sort( { name : 1 } )

 Ans.

2. var c = db.products.find( { }, { name : 1, _id : 0 } ).sort( { name : 1 } ); while( c.hasNext() ) { print( c.next().name); }

3. var c = db.products.find( { } ).sort( { name : 1 } ); c.forEach( function( doc ) { print( doc.name ) } );

4. db.products.find( { }, { name : 1, _id : 0 } ).sort( { name : 1 } )

Quiz: Concepts

Quiz: Concepts

What were the big differences in hardware over the last few decades that MongoDB attempted to address?

Parallelism of coresParallelism of serversQuantum computersFaster clock speedsMore memoryScaling

Q: When scaling out horizontally (adding more servers to contain your data), what are problems that arise as you go from, say, 1 commodity server to a few dozen?

The original server, if incorporated into the cluster, is more likely to fail in a given unit of time than if it had been left as a single server.The servers must communicate with one another eating up network bandwidthThe need for redundancy increases as the likelihood of some failure in the system per unit of time increases.Hardware cost per server is likely to increase.

Overview of MondoDB Advance, Administrative commands of mongoDB.

Query Language Cursors in MongoDB,

Sorting in mongoDB using shell query.

Example of MongoDB shell query.

Shell query of mongoDB,

Advantage of mongoDB query Language in dynamic schema.

Query projection in mongodb.

Query of mongoDB basics.

Cursors introductions in mongoDB

Import json and data in MongoDB

Introduction of MongoDb Shell

Dynamic schema in mongoDb

Dynamic BSON

Binary Json introduction

Json RFC Rule and replication in json

Json to XML Conversion

Data types in json

Installing MongoDB windows versions

Installing Mongodb on mac

Introduction of mongodb

Course overview for DBA

welcome to mongodb tutorials