Mongo Db基本查询

gt: 大于
gte:大于等于
lt:小于
lte:小于等于
SQL 查询语句 
MongoDB find() 语句
SELECT * FROM users 
db.users.find()
SELECT id, user_id, status FROM users 
db.users.find( { }, { user_id: 1, status: 1 } )
SELECT user_id, status FROM users 
db.users.find( { }, { user_id: 1, status: 1, _id: 0 } )
SELECT * FROM users WHERE status = "A" 
db.users.find( { status: "A" } )
SELECT user_id, status FROM users WHERE status =
"A"
db.users.find( { status: "A" }, { user_id: 1, status: 1,
_id: 0 } )
SELECT * FROM users WHERE status != "A" 
db.users.find( { status: { $ne: "A" } } )
SELECT * FROM users WHERE status = "A" AND
age = 50
db.users.find( { status: "A", age: 50 } )
SELECT * FROM users WHERE status = "A" OR age
= 50
db.users.find( { $or: [ { status: "A" } , { age: 50 } ] } )
SELECT * FROM users WHERE age > 25 
db.users.find( { age: { $gt: 25 } } )
SELECT * FROM users WHERE age < 25 
db.users.find( { age: { $lt: 25 } } )
SELECT * FROM users WHERE age > 25 AND age
<= 50
db.users.find( { age: { $gt: 25, $lte: 50 } } )
SELECT * FROM users WHERE user_id like "%bc%" 
db.users.find( { user_id: /bc/ } )
SELECT * FROM users WHERE user_id like "bc%" 
db.users.find( { user_id: /^bc/ } )
SELECT * FROM users WHERE status = "A" ORDER
BY user_id ASC
db.users.find( { status: "A" } ).sort( { user_id: 1 } )
SELECT * FROM users WHERE status = "A" ORDER
BY user_id DESC
db.users.find( { status: "A" } ).sort( { user_id: -1 } )
SELECT COUNT(*) FROM users 
db.users.count()
or
db.users.find().count()
SELECT COUNT(user_id) FROM users 
db.users.count( { user_id: { $exists: true } } )
or
db.users.find( { user_id: { $exists: true } } ).count()
SELECT COUNT(*) FROM users WHERE age > 30 
db.users.count( { age: { $gt: 30 } } )
or索引
db.stores.createIndex( { name: "text", description: "text" } )
db.stores.find( { $text: { $search: "java coffee shop" } } )
精确查找
db.stores.find( { $text: { $search: "java \"coffee shop\"" } } )
为了排除一个词语，您可以在前面加上一个 “-” 字符。例如，为了找到所有包含 “java” 或者 “shop” 但
是不包含 “coffee” 的商店，使用下面的命令：
db.stores.find( { $text: { $search: "java shop -coffee" } } )
db.users.find( { age: { $gt: 30 } } ).count()
SELECT DISTINCT(status) FROM users 
db.users.distinct( "status" )
SELECT * FROM users LIMIT 1 
db.users.findOne()
or
db.users.find().limit(1)
SELECT * FROM users LIMIT 5 SKIP 10 
db.users.find().limit(5).skip(10)
EXPLAIN SELECT * FROM users WHERE status = "A" db.users.find( { status: "A" } ).explain()