Node. js and MongoDB tutorial

First of all to ensure that the correct installation of mongodb, Installation Reference: http://docs.mongodb.org/manual/tutorial/install-mongodb-on-debian-or-Ubuntu-linux

Then download the mongodb driver of nodejs

Npm install mongodb

Compile a test program:

Var mongodb = require ('mongodb ');
Var server = new mongodb. Server ('localhost', 27017, {auto_reconnect: true });
Var db = new mongodb. Db ('mydb', server, {safe: true });
Db. open (function (err, db ){
If (! Err)
{
Console. log ('connect ');
} Else {
Console. log (err );
}
 
});

If "connect" is displayed, the connection is successful.

Operations on collection of mongodb

There are two methods to link collection:

Db. collection ('mycoll ', function (err, coll ){});

Db. createCollection ('mycoll ', function (err, coll ){});

The two methods have the second optional parameter {safe: true}. this parameter is used for the first method. If this parameter is added, an error is returned when the collection does not exist, for the second method, an error is reported when the collection exists.

Example:

Var mongodb = require ('mongodb ');
Var server = new mongodb. Server ('localhost', 27017, {auto_reconnect: true });
Var db = new mongodb. Db ('mydb', server, {safe: true });
Db. open (function (err, db ){
If (! Err)
{
Console. log ('connect ');
Db. collection ('mycoll ', {safe: true}, function (err, collection ){
If (err ){
Console. log (err );
}
});
 
} Else {
Console. log (err );
}
 
});

Result:

Example:

Var mongodb = require ('mongodb ');
Var server = new mongodb. Server ('localhost', 27017, {auto_reconnect: true });
Var db = new mongodb. Db ('mydb', server, {safe: true });
Db. open (function (err, db ){
If (! Err)
{
Console. log ('connect ');
Db. createCollection ('mycoll ', {safe: true}, function (err, collection ){
If (err ){
Console. log (err );
}
});
 
} Else {
Console. log (err );
}
 
});

Result:

 

To delete a collection, use the dropCollection function:

Example:

Var mongodb = require ('mongodb ');
Var server = new mongodb. Server ('localhost', 27017, {auto_reconnect: true });
Var db = new mongodb. Db ('mydb', server, {safe: true });
Db. open (function (err, db ){
If (! Err)
{
Console. log ('connect ');
Db. dropCollection ('mycoll ', {safe: true}, function (err, result ){
Console. log (result );
});
 
} Else {
Console. log (err );
}
});

Result:

Add, delete, modify, and query collections

1 2 3 Next Page