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連接數(shù)據(jù)庫

代碼如下:

var mongo=require("mongodb");

var host="localhost";

var port=mongo.Connection.DEFAULT_PORT;

var server=new mongo.Server(host,port,{auto_reconnect:true});//創(chuàng)建數(shù)據(jù)庫所在的服務(wù)器服務(wù)器

var db=new mongo.Db("node-mongo-examples",server,{safe:true});//創(chuàng)建數(shù)據(jù)庫對象

db.open(function (err,db) {//連接數(shù)據(jù)庫

if(err)

throw err;

else{

console.log("成功建立數(shù)據(jù)庫連接");

db.close();

}

});

db.on("close", function (err,db) {//關(guān)閉數(shù)據(jù)庫

if(err) throw err;

else console.log("成功關(guān)閉數(shù)據(jù)庫.");

});

插入數(shù)據(jù):

插入數(shù)據(jù)后,在控制臺中輸出數(shù)據(jù)文檔的內(nèi)容

代碼如下:

var mongo=require("mongodb");

var host="localhost";

var port=mongo.Connection.DEFAULT_PORT;

var server=new mongo.Server(host,port,{auto_reconnect:true});//創(chuàng)建數(shù)據(jù)庫所在的服務(wù)器服務(wù)器

var db=new mongo.Db("node-mongo-examples",server,{safe:true});//創(chuàng)建數(shù)據(jù)庫對象

db.open(function (err,db) {//連接數(shù)據(jù)庫

if(err)

throw err;

else{

db.collection("users", function (err,collection) {

collection.insert({username:"盼盼",firstname:"李"}, function (err,docs) {

console.log(docs);

db.close();

});

});

}

});

db.on("close", function (err,db) {//關(guān)閉數(shù)據(jù)庫

if(err) throw err;

else console.log("成功關(guān)閉數(shù)據(jù)庫.");

});

關(guān)閉數(shù)據(jù)庫db.close([forceClose],[callback]);

forceClose為true時,強(qiáng)制關(guān)閉該數(shù)據(jù)庫,當(dāng)數(shù)據(jù)庫關(guān)閉后,不可再使用open開啟數(shù)據(jù)庫.

forceClose為false時,不強(qiáng)制關(guān)閉數(shù)據(jù)庫,當(dāng)數(shù)據(jù)庫關(guān)閉后,可以再使用open打開.

當(dāng)foreClose為true時:

代碼如下:

var mongo=require("mongodb");

var host="localhost";

var port=mongo.Connection.DEFAULT_PORT;

var server=new mongo.Server(host,port,{auto_reconnect:true});//創(chuàng)建數(shù)據(jù)庫所在的服務(wù)器服務(wù)器

var db=new mongo.Db("node-mongo-examples",server,{safe:true});//創(chuàng)建數(shù)據(jù)庫對象

db.open(function (err,db) {//連接數(shù)據(jù)庫

if(err)

throw err;

else{

db.collection("users", function (err,collection) {

collection.insert({username:"盼盼",firstname:"李"}, function (err,docs) {

console.log(docs);

db.close(false);

});

});

}

});

db.once("close", function (err,db) {//關(guān)閉數(shù)據(jù)庫

if(err) throw err;

else {

db.open(function (err,db) {

db.collection("users", function (err,collection) {

collection.insert({username:"三",firstname:"張"}, function (err,docs) {

if(err) throw err;

else{

console.log(docs);

db.close(true);

}

})

});

});

}

});

//讀取數(shù)據(jù)

代碼如下:

var mongo=require("mongodb");

var host="localhost";

var port=mongo.Connection.DEFAULT_PORT;

var server=mongo.Server(host,port,{auto_reconnect:true});

var db=new mongo.Db("node-mongo-examples",server,{safe:true});

db.open(function (err,db) {

db.collection("users", function (err,collection) {

if(err) throw err;

else{

collection.find({}).toArray(function(err,docs){

if(err) throw err;

else{

console.log(docs);

db.close();

}

});

}

});

});

//帶查詢條件的搜索

代碼如下:

var mongo=require("mongodb");

var host="localhost";

var port=mongo.Connection.DEFAULT_PORT;

var server=mongo.Server(host,port,{auto_reconnect:true});

var db=new mongo.Db("node-mongo-examples",server,{safe:true});

db.open(function (err,db) {

db.collection("users", function (err,collection) {

if(err) throw err;

else{

collection.find({username:{$in:["延思","三"]}}).toArray(function(err,docs){

if(err) throw err;

else{

console.log(docs);

db.close();

}

});

}

});

});

//插入一批數(shù)據(jù),并且進(jìn)行搜索type==food且price字段值小于10

代碼如下:

var mongo=require("mongodb");

var host="localhost";

var port=mongo.Connection.DEFAULT_PORT;

var server=mongo.Server(host,port,{auto_reconnect:true});

var db=new mongo.Db("node-mongo-examples",server,{safe:true});

var docs=[

{type:"food",price:11},

{type:"food",price:10},

{type:"food",price:9},

{type:"food",price:8},

{type:"book",price:9}

];

db.open(function (err,db) {

db.collection("goods", function (err,collection) {

if(err) throw err;

else{

collection.insert(docs, function (err,docs) {

if(err) throw err;

else{

collection.find({type:"food",price:{$lt:10}}).toArray(

function(err,docs){

if(err) throw err;

else{

console.log(docs);

db.close();

}

}

);

}

})

}

});

});

查詢中的或的表達(dá):

代碼如下:

collection.find({$or:[

　　　　{type:"food"},

　　　　{price:{$lt:10}}

　　]})

有關(guān)node.js操作mongoDB數(shù)據(jù)庫的講解，今天就先到這里了，基本上常用的操作都有了示例，復(fù)雜些的，小伙伴們自由發(fā)揮吧，有機(jī)會我們再來繼續(xù)講解。

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