MongoDB语法与SQL语法比较

MongoDB语法                                   MySql语法
db.test.find({'name':'foobar'})            <==> select * from test where name='foobar'
db.test.find()                                     <==> select * from test
db.test.find({'ID':10}).count()             <==> select count(*) from test where ID=10
db.test.find().skip(10).limit(20)          <==> select * from test limit 10,20
db.test.find({'ID':{$in:[25,35,45]}})     <==> select * from test where ID in (25,35,45)
db.test.find().sort({'ID':-1})                <==> select * from test order by ID desc
db.test.distinct('name',{'ID':{$lt:20}})  <==> select distinct(name) from test where ID<20

db.test.group({key:{'name':true},cond:{'name':'foo'},reduce:function(obj,prev){prev.msum+=obj.marks;},initial:{msum:0}}) 

                                                          <==> select name,sum(marks) from test group by name

db.test.find('this.ID<20',{name:1})     <==> select name from test where ID<20

db.test.insert({'name':'foobar','age':25})<==>insert into test ('name','age') values('foobar',25)

db.test.remove({})                              <==> delete * from test
db.test.remove({'age':20})                 <==> delete test where age=20
db.test.remove({'age':{$lt:20}})          <==> elete test where age<20
db.test.remove({'age':{$lte:20}})        <==> delete test where age<=20
db.test.remove({'age':{$gt:20}})         <==> delete test where age>20
db.test.remove({'age':{$gte:20}})       <==> delete test where age>=20
db.test.remove({'age':{$ne:20}})         <==> delete test where age!=20

db.test.update({'name':'foobar'},{$set:{'age':36}}) <==> update test set age=36 where name='foobar'
db.test.update({'name':'foobar'},{$inc:{'age':3}}) <==> update test set age=age+3 where name='foobar'

 

 

sql语法和MongoDB语法的对应关系

sql语法和MongoDB语法的对应关系

SQL Statement	Mongo Query Language Statement
CREATE TABLE USERS (a Number, b Number)	db.createCollection("mycoll", {capped:true, size:100000})
INSERT INTO USERS VALUES(1,1)	db.users.insert({a:1,b:1})
SELECT a,b FROM users	db.users.find({}, {a:1,b:1})
SELECT * FROM users	db.users.find()
SELECT * FROM users WHERE age=33	db.users.find({age:33})
SELECT a,b FROM users WHERE age=33	db.users.find({age:33}, {a:1,b:1})
SELECT * FROM users WHERE age=33 ORDER BY name	db.users.find({age:33}).sort({name:1})
SELECT * FROM users WHERE age>33	db.users.find({'age':{$gt:33}})})
SELECT * FROM users WHERE age<33	db.users.find({'age':{$lt:33}})})
SELECT * FROM users WHERE name LIKE "%Joe%"	db.users.find({name:/Joe/})
SELECT * FROM users WHERE name LIKE "Joe%"	db.users.find({name:/^Joe/})
SELECT * FROM users WHERE age>33 AND age<=40	db.users.find({'age':{$gt:33,$lte:40}})})
SELECT * FROM users ORDER BY name DESC	db.users.find().sort({name:-1})
CREATE INDEX myindexname ON users(name)	db.users.ensureIndex({name:1})
CREATE INDEX myindexname ON users(name,ts DESC)	db.users.ensureIndex({name:1,ts:-1})
SELECT * FROM users WHERE a=1 and b='q'	db.users.find({a:1,b:'q'})
SELECT * FROM users LIMIT 10 SKIP 20	db.users.find().limit(10).skip(20)
SELECT * FROM users WHERE a=1 or b=2	db.users.find( { $or : [ { a : 1 } , { b : 2 } ] } )
SELECT * FROM users LIMIT 1	db.users.findOne()
EXPLAIN SELECT * FROM users WHERE z=3	db.users.find({z:3}).explain()
SELECT DISTINCT last_name FROM users	db.users.distinct('last_name')
SELECT COUNT(*y) FROM users	db.users.count()
SELECT COUNT(*y) FROM users where AGE > 30	db.users.find({age: {'$gt': 30}}).count()
SELECT COUNT(AGE) from users	db.users.find({age: {'$exists': true}}).count()
UPDATE users SET a=1 WHERE b='q'	db.users.update({b:'q'}, {$set:{a:1}}, false, true)
UPDATE users SET a=a+2 WHERE b='q'	db.users.update({b:'q'}, {$inc:{a:2}}, false, true)
DELETE FROM users WHERE z="abc"	db.users.remove({z:'abc'});