10. MongoDB - CRUD operations - select the fields using dot notation

dba@HP:~$ mongo university
MongoDB shell version: 2.4.9
connecting to: university
> show collections
info
name
result
system.indexes
>

/* insert three document for 'db' =>uiversity and 'collection' => info  */
> db.info.insert({ "_id" : "mohamedzajith", "age" : 24, "email" : { "personal" : "mohamedzajith@uojonline.net", "offcial" : "mohamedzajith@gmail.com" }, "address" : { "street" : "campus lane", "city" : "jaffna", "country" : "srilanka" } })

> db.info.insert({ "_id" : "nimishan", "age" : 23, "email" : { "personal" : "nimishan.siv@gmail.com", "offcial" : "nimishan@live.com" }, "address" : { "street" : "bandarawela", "city" : "badulla", "country" : "srilanka" } })

> db.info.insert({ "_id" : "fahimfana", "age" : 22, "email" : { "personal" : "mohamedfahim91@gmail.com", "offcial" : "fahimfana91@gmail.com" }, "address" : { "street" : "hettuwewa", "city" : "anuradapura", "country" : "srilanka" } })

/* find the all document from info collection  */
> db.info.find()
{ "_id" : "mohamedzajith", "age" : 24, "email" : { "personal" : "mohamedzajith@uojonline.net", "offcial" : "mohamedzajith@gmail.com" }, "address" : { "street" : "campus lane", "city" : "jaffna", "country" : "srilanka" } }
{ "_id" : "nimishan", "age" : 23, "email" : { "personal" : "nimishan.siv@gmail.com", "offcial" : "nimishan@live.com" }, "address" : { "street" : "bandarawela", "city" : "badulla", "country" : "srilanka" } }
{ "_id" : "fahimfana", "age" : 22, "email" : { "personal" : "mohamedfahim91@gmail.com", "offcial" : "fahimfana91@gmail.com" }, "address" : { "street" : "hettuwewa", "city" : "anuradapura", "country" : "srilanka" } }

/* select 'email' filed from info collection  */
> db.info.find({"email" : { "personal" : "mohamedzajith@uojonline.net"}})

> db.info.find({"email" : { "personal" : "mohamedzajith@uojonline.net", "offcial" : "mohamedzajith@gmail.com"}})
{ "_id" : "mohamedzajith", "age" : 24, "email" : { "personal" : "mohamedzajith@uojonline.net", "offcial" : "mohamedzajith@gmail.com" }, "address" : { "street" : "campus lane", "city" : "jaffna", "country" : "srilanka" } }

/* select 'email' filed from info collection use pretty method */
> db.info.find({"email" : { "personal" : "mohamedzajith@uojonline.net", "offcial" : "mohamedzajith@gmail.com"}}).pretty()
{
"_id" : "mohamedzajith",
"age" : 24,
"email" : {
"personal" : "mohamedzajith@uojonline.net",
"offcial" : "mohamedzajith@gmail.com"
},
"address" : {
"street" : "campus lane",
"city" : "jaffna",
"country" : "srilanka"
}
}

/* select 'email' filed from info collection using dot notation   */
> db.info.find({"email.personal" : "mohamedzajith@uojonline.net"})
{ "_id" : "mohamedzajith", "age" : 24, "email" : { "personal" : "mohamedzajith@uojonline.net", "offcial" : "mohamedzajith@gmail.com" }, "address" : { "street" : "campus lane", "city" : "jaffna", "country" : "srilanka" } }

> db.info.find({"email.personal" : "mohamedzajith@uojonline.net"}).pretty()
{
"_id" : "mohamedzajith",
"age" : 24,
"email" : {
"personal" : "mohamedzajith@uojonline.net",
"offcial" : "mohamedzajith@gmail.com"
},
"address" : {
"street" : "campus lane",
"city" : "jaffna",
"country" : "srilanka"
}
}