MonogoDB

mongo是noSQL(lessSQL)的資料庫

find及findOne指令

查詢返回特定的欄位

db.users.findOne({"欄位","查詢值",[{欄位:是否傳回}]});

sql:
select age,sex from users where name='123';
mongo:
db.users.findOne({"name":"123"},{"age":1,"sex":1});

db.users.findOne({'source.id":'123','source.site':'google'});