2. ABSTRACT
This PPT will explain about the MONGODB concepts and using that can
achieve the CURD Operation.
3. What is MongoDB
It is a Open source cross platform document oriented with the scalability
and flexible database.
MongoDB is a distributed database at its core, so high availability,
horizontal scaling, and geographic distribution are built in and easy to use.
Its Classified as NOSQL database program.
There is no RDBMS Concept here and data’s are stored in a flat file system.
MongoDB uses JSON-like documents with SCHEMA for creating a new
Table in the DB.
4. Key Features:
High Performance:
Support for embedded data models reduces I/O activity on database system.
Indexes support faster queries and can include keys from embedded documents and
arrays.
Rich Query Language.
High Availability: Automatic failover and data redundancy.
Horizontal Scalability :
Sharding distributes data across a cluster of machines.
MongoDB 3.4 supports creating zones of data based on the shard key. In a balanced
cluster, MongoDB directs reads and writes covered by a zone only to those shards inside
the zone. See the Zones manual page for more information.
5. Support for Multiple Storage Engines:
WiredTiger Storage Engine
MMAPV1 Storage Engine
Creating dummy Collection
Example :
export var dummytable= new Mongo.Collection(null);
6. Where we use the MongoDB
You need High Availability in an Unreliable Environment (Cloud and Real
Life)
You need to Grow Big (and Shard Your Data)
Your Data is Location Based
Your Data Set is Going to be Big (starting from 1GB) and Schema is Not
Stable
You Don't have a DBA
9. Installation Steps for MongoDB
It will support all Operating System. The below links will used for install the
mongoDB
https://docs.mongodb.com/manual/installation/
https://www.mongodb.com/
10. CREATE A NEW TABLE
We have a create a new table in MongoDB using Schema.
In that Schema it self we can add fields and there properties of the table.
Sample Schema for create a new table in Mongo DB. File name eg :
SampleDB.js
11. var sampletable= new SimpleSchema({
id: {
type: Number,
label: "ID",
optional: true //It mean the field is Mandatory
},
name: {
type: String,
label: "Name",
optional: true
},
bloodgroup: {
type: String,
label: "BloodGroup",
},
phonenumber: {
type: Number,
label: "Phone Number",
optional: true
},
Date: {
type: Date,
label: "Phone Number",
optional: true
},
});
export const Test = new Mongo.Collection('test');
Test.attachSchema(sampletable);
12. STORE THE VALUE
We can store the Value in MongoDB , using INSERT command.
If we pass a array we can store in to Database.
The below example contains both array and list the fields are passing to
store the value in Database.
Example : Array value is storing in DB
14. QUERY THE RECORD
To read or query the record in the MongoDB , here its named as finding the record .
We have to use find(), fetch(), count() and findAll() methods for search the value in
the table.
find() : It will find the particular record for that we have to pass the _id unique
address of the record.
fetch() : It will fetch the value for a particular record that we have to pass the _id
unique address of the record.
count() : It will query the records based on the counts.
Syntax:
find() and fetch()
db.collection_name.find({ObjectId(12 digit hashcode)}).fetch();
find() and count()
db.collection_name.find({ObjectId(12 digit hashcode)}).count();
16. UPDATE THE VALUE
For Update the existing record in the MongoDB , we have to use UPDATE
command .
We can able to update group of record as well as particular record.
Syntax:
db.collection_name.update({ _id:’value’,fieldname:fieldvalue });
Example:
test.update({ _id: 7df78ad8902c,phonenumber:’+91-8825719818’})
17. REMOVE (or)DELETE THE RECORD
To delete the records in the collection will use REMOVE and DELETE command.
REMOVE:
It will remove single or multiple the records in the collection the details as below.
SYNTAX:
db.collection_name.remove({_id});
To remove the multiple records in the collection use the below logic.
Logic:
var noofrecord= db.collection_name.find().count();
for (i=0;i< noofrecord;i++){
var idval= i._id
db.collection_name.remove({idval});
}
18. DELETE:
It will delete single or multiple record in the collection the details as mentioned the below.
SYNTAX:
Delete a single record in the collection.
db.collection_name.deleteOne({_id:ObjectId(“12 digit hash”)});
Example:
db.test.deleteOne({_id:ObjectId(“838383837312”)});
Delete multiple records in the collection.
db.collection_name.deleteMany({fieldname:fieldvalue)});
Example:
db.test.deleteMany({bloodgroup:’0+ve’)});
19. DROP THE TABLE
Using the drop() predefined method will able to delete the entire
collection.
The below example is explaining about the delete the collection.
Example:
test.drop()
