Official mongodb documentation
Once you have mongodb installed you can run mongodb server with comand
mongod
In some UNIX systems the folder /data/db
must be creates or you can specify another folder to store mongodb databases.
mongod --dbpath Documents/db
For more options you can run mongo options you can run
mongo -h
Once you have mongodb running then you can run mongo
command in your terminal, by default you'll be connected to localhost using port 27017
mongo
mongo use databaseName
If you want to connect to a remote mongodb server then you have to specify host, port, user, password and database name.
mongo <host>:<port>/<database> -u <dbuser> -p <dbpassword>
eg:
mongo ds159033.mlab.com:59033/example-db -u read-user -p securepsw
To insert you can specify a sinlge object or an array of objects, eg:
db.collectionName.insert(document || document[]);
db.collectionName.insertOne(domcument);
db.collectionName.insertMany(document[]);
db.collectionName.save(document);
To read a collection you can filter and project the find function, eg:
db.collectionName.find(where, projection);
Projection is the set of field to include/exclude in the cursor
To update documents in a collection you can use the updates methods:
db.collectionName.update(where, document || document[], options);
db.collectionName.updateOne(where, document, options);
db.collectionName.updateMany(where, document[], options);
To delete documents in a collection you can use the remove method
db.collectionName.remove(where, options);
To import data to mongodb you can user two different commands mongorestore
and mongoimport
.
mongorestore
restores data exported with indexes and metadata, the restored data should be a result of mongodump
mongorestore -d database folderName
mongorestore -d database -collection collection file.bson
mongorestore -h remoteServer -d database -u user -p password folderName
mongoimport
creates or updates documents from json, csv or tsv files, a collection should be specified, no indexes and no metadata should be imported
mongoimport -d database -c collectionName file.json
mongoimport -h remoteServer -d database -c collection -u user -p password file.json
To export data from mongodb you can use mongodump
and mongoexport
.
mongodump
will export all the data in the database including indexes and metadata
mongodump -d database -o outputDir
mongodump -d database -c collection -o outputDir
mongoexport exports only data from a collection
mongoexport -d database -c collectionName file.json
mongoexport -h remoteServer -d database -c collection -u user -p password file.json
Get indexes
db.collectionName.getIndexes();
db.movieDetails.getIndexes();
Simple index
db.collectionName.createIndex(keys, options);
db.movieDetails.createIndex({rated:1}, {sparse:1});
Compund index
db.movieDetails.createIndex({"awards.nominations":1});
Multikey index
db.movieDetails.createIndex({rated:1, metacritic: 1});
Text index:
db.movies.createIndex( { title: "text" } );
db.movieDetails.createIndex({title:"text", plot:"text", actors:"text"}, {weights: {title:10, actors:5}, name:"textIndex"})
db.movieDetails.find({$text:{$search:"Leo"}}, {score:{$meta:"textScore"}}).sort({score:{$meta:"textScore"}}).limit(5).pretty();
2d Spatial index
db.collection.createIndex({location:"2d"});
db.collection.find({location:{$near:[50, 50]}})
Delete index
db.collectionName.dropIndex(indexName);
Covered queries
db.movieDetails.explain("executionStats").find({rated:'PG',metacritic:'71'}, {_id:0});