MongoDB -- Collections

Creation of Collections:

we use tables in the traditional databases, here we use collections, the columns are called as fields, and joins are embedded documents.

lets create a simple collection:

first create a database: use dataset

then check the db: db

create a simple collection:
command: db.createCollection("customers")
 output : {ok:1}

we call record as documents here:
now insert a document in collection "dataset":

command:db.customers.insert({'name':'raj'})

to see the columns or data in tables we use select statement , here we use find() method.

command:db.customers.find()
output: ("_id":ObjectId(568cbca55685654adasda),"name":"raj")
 here the id for each field is created automatically, it is index of the field.


if you want the structure formatted of the document: use the following command:
command: db.customers.find().pretty()