var x=new Mongo("192.168.2.4:27017")

show dbs

var db=x.getDB("background")

db.getName()

db.getCollectionNames()

db.getCollectionInfos()

db.getCollection("background")

db.getCollection("background").count()

db.hostInfo()

db.getMongo()

db.TableName.ensureIndex({FieldName:1})//1為升(sheng)序，-1為降序
db.TableName.getIndexes()

db.TableName.dropIndex({"LoginName":1})

db.WebManageUsers.stats()

db.stats()

var db=x.getDB("admin");
db.runCommand({listshards:1});//需要在admin數(shu)據庫(ku)下

#指定databaseName分片生效
db.runCommand( { enablesharding :"databaseName"});

#指(zhi)定數據庫里需要分(fen)片的集合和片鍵
db.runCommand( { shardcollection : "databaseName.tableName",key : {_id: 1} } )

db.tableName.aggregate([{ "$group" : { "_id" : "$DepartmentID", "userCount" : { "$sum" : 1 } } }])

db.M_Partner_Footprints.group({
    key: function (doc) { PartnerInfoID: true },//分組的key
    cond: { PartnerInfoID: 6, Login: { ClientType: 0 } },//條件過濾
    initial: { "count": 0 },
    reduce: function (doc, out) {//聚(ju)合方式
        out.count += 1;
    },
    finalize: function (out) {//結果處(chu)理(li)
        return out;
    }
});

db.M_User_Footprints.group({
    keyf: function (doc) { return { UserInfoID: doc.UserInfoID, TeacherID: doc.TeacherID } },
    cond: { UserInfoID: 6, Type: 6 },
    initial: { "count": 0 },
    reduce: function (doc, out) {
        out.count += 1;
    },
    finalize: function (out) {
        return out;
    }
});

db.M_User_Footprints.aggregate([{ $group: { _id: "$UserInfoID", num_tutorial: { $sum: 1 } } }])

db.M_User_Footprints.aggregate(
    {
        $project: {
            UserInfoID: 1,
            TeacherID: 1,
        }
    }
 );

db.M_User_Footprints.aggregate([
                        { $match: { UserInfoID: { $gt: 1, $lte: 100 } } },
                        { $group: { _id: null, count: { $sum: 1 } } }
]);