show dbsio
show tablestable
show collectionsim
use userdb
db.createCollection('config_collection')img
use usertab
db.user_collection.insert({username:'tom'}) co
db.user_collection.insertOne({username: jhoe})config
use userab
db.dropDatabase() 格式化
use user
db.user_collection.drop()
use user
db.config_collection.find()
db.config_collection.findOne()
db.config_collection.find().pretty() //格式化顯示