Walkthrough

Great page SQL vs. NoSQL

db.bibliotek.insert{}

Insert a variable into a collection.

var bog =

{
    "ISBN" : 12.0,
        "titel" : "Birdsong",
        "forfatter" : "Sebastian Faulk",
        "format" : "ebog",
        "pris" : 6.0
}

db.bibliotek.insert({bog})

Save it. Another way to insert collections.

db.bibliotek.save(
{
    "ISBN" : 13.0,
        "titel" : "The Woman in White",
        "forfatter" : "Wilkie Collins",
        "format" : "ebog",
        "pris" : 9.0
})

Another book

db.bibliotek.save(
    {
    "ISBN" : 13.0,
    "titel" : "Lord of the Flies",
    "forfatter" : "William Golding",
    "format" : "ebog",
    "pris" : 9.0
    })

Query - Where ISBN: 13

db.('bibliotek').find({ISBN:13})

Query - Where ISBN i greater than 1, and less than 13. db.bibliotek.find({ISBN: {$gt: 1, $lt: 13}})

Update - Change ISBN from 13 to 18

db.bibliotek.update({ISBN: 13}, {$set:{ISBN: 18}})

Sort

db.bibliotek.find().sort({ISBN:-1})

In

db.bibliotek.find({ISBN: {$in: [1,2,15]}})

Comparison SQL vs MongoDB

|          |          |
|----------|----------|
| WHERE    | $match   |
| GROUP BY | $group   |
| HAVING   | $match   |
| SELECT   | $project |
| ORDER BY | $sort    |
| LIMIT    | $limit   |
| SUM      | $sum     |
| COUNT    | $sum     |
| JOIN     | $unwind  |

Aggregate

db.ships.aggregate([$group: {_id: "Klingon Empire", skibe: {$sum: "$crew"}}}])

SQL vs. MongoDB

database                -->            database
table                   -->            collection
row                     -->            document or BSON document
column                  -->            field
index                   -->            index
table joins             -->            embedded documents & linking
where                   -->            $match
group by                -->            $group
count()                 -->            $sum
order by                -->            $sort
limit()                 -->            $limit
select                  -->            $project
having                  -->            $match

Alter a table (SQL)/Collection(MongoDB)

SQL:
     Alter table users ADD location Varchar(255);

MongoDB:
     db.users.update(
         {user_id: 'Pranava'},
         {$set: { location: 'Bharat'},
         {multi: true}
     )

Select specific columns in a table(Sql)/Collection(MongoDB)

SQL:

         SELECT user_id, age from users;

MongoDB: db.users.find({},{user_id: 1, status: 1});

Add a condition to choose which field you want to output.

    db.bibliotek.find({ISBN: 1}, {titel: 1})

And query

SQL: SELECT * from bibliotek where titel='Lord of the Flies' and format='ebog';

MongoDB

    db.bibliotek.find({titel: "Lord of the Flies",format: "ebog"})

Query Or - The titel is either The Great Gatsby or the author is F Scott Fitzgerald.

db.bibliotek.find({$or: [{titel: "The Great Gatsby"}, {forfatter: "F Scott Fitzgerald"}]})