mongo

導入導出

mongodb導出

./mongoexport --db ***db  -c dingdianbookcoll -o ***coll.json

mongodb導入

mongoimport   -d ***db  -c ***coll --file ***coll.json   --type json

新增字段

from utils.config import MONG_CONN

testdb = MONG_CONN['test']
peoplecol = testdb["people"]

icount=0
for item in peoplecol.find():
    icount+=1
    print(item)
    peoplecol.update({"_id":item['_id']},{"$set":{"last_chapter":str(icount)+item['name']}})

是否存在

db.users.find({age: {$exists: true}});

修改列名

db.getCollection('***col').update({},{$rename:{"Id":'Uid'}},false,true)

db.tickets.renameCollection(“tickets_bak20130510”);

service mongod stop
checkconfig mongod on

db.***rcol.aggregate([{'$group':{
                                    '_id':{'Bid' :'$Bid','Cid' :'$Cid'},
                                    'uniqueIds':{'$addToSet':'$_id'},
                                    'count':{'$sum':1}
                            }},
                            {'$match':{'count':{'$gt':1} 
                            }}],
                           {allowDiskUse:true}
                        )

db.***col.aggregate([
    {
        $group: { _id: {Bid: '$Bid',Cid: '$Cid'},count: {$sum: 1},dups: {$addToSet: '$_id'}}
    },
    {
        $match: {count: {$gt: 1}}
    }
],{ allowDiskUse: true }).forEach(function(doc){
    doc.dups.shift();
    db.***rcol.remove({_id: {$in: doc.dups}});
})

修改數據庫的collection名

db.adminCommand({renameCollection: "db.collection1", to: "db.collection2"})

mod批量更新

db.jiastonbooklistcol29.update({Uid:{$mod:[8,0]}},{$set:{"hostname":"***08"}},false,true)