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cursor.js
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cursor.js
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var Db = require('../lib/mongodb').Db
, Connection = require('../lib/mongodb').Connection
, Server = require('../lib/mongodb').Server
, format = require('util').format;
var host = process.env['MONGO_NODE_DRIVER_HOST'] != null ? process.env['MONGO_NODE_DRIVER_HOST'] : 'localhost';
var port = process.env['MONGO_NODE_DRIVER_PORT'] != null ? process.env['MONGO_NODE_DRIVER_PORT'] : Connection.DEFAULT_PORT;
console.log("Connecting to " + host + ":" + port);
Db.connect(format("mongodb://%s:%s/node-mongo-examples?w=1", host, port), function(err, db) {
db.collection('test', function(err, collection) {
// Erase all records from collection, if any
collection.remove(function(err, result) {
// Insert 3 records
for(var i = 0; i < 3; i++) {
collection.insert({'a':i}, {w:0});
}
// Cursors don't run their queries until you actually attempt to retrieve data
// from them.
// Find returns a Cursor, which is Enumerable. You can iterate:
collection.find().each(function(err, item) {
if(item != null) console.dir(item);
});
// You can turn it into an array
collection.find().toArray(function(err, items) {
console.log("count: " + items.length);
});
// You can iterate after turning it into an array (the cursor will iterate over
// the copy of the array that it saves internally.)
var cursor = collection.find();
cursor.toArray(function(err, items) {
cursor.each(function(err, item) {
if(item != null) console.dir(item);
});
});
// You can get the next object
collection.find().nextObject(function(err, item) {
if(item != null) console.dir(item);
});
// next_object returns null if there are no more objects that match
var cursor = collection.find();
cursor.nextObject(function(err, item) {
cursor.nextObject(function(err, item) {
cursor.nextObject(function(err, item) {
cursor.nextObject(function(err, item) {
console.log("nextObject returned: ");
console.dir(item);
db.close();
});
});
});
});
});
});
});