下面是官方的比对，很清晰明了
更多资料：http://www.mongodb.org/display/DOCS/Manual
SQL to Mongo Mapping Chart
| MySQL executable | Oracle executable | Mongo executable |
|---|---|---|
| mysqld |
oracle |
mongod |
| mysql |
sqlplus |
mongo |
| MySQL term | Mongo term |
|---|---|
| database | database |
| table | collection |
| index | index |
| row | BSON document |
| column | BSON field |
| join | embedding and linking |
| primary key | _id field |
MongoDB queries are expressed as JSON (BSON) objects. The following chart shows examples as both SQL and in Mongo Query Language syntax.
The query expression in MongoDB (and other things, such as index key patterns) is represented as JSON (BSON). However, the actual verb (e.g. "find") is done in one's regular programming language; thus the exact forms of these verbs vary by language. The
examples below are Javascript and can be executed from the
mongo shell.
| SQL Statement |
Mongo Statement |
|---|---|
CREATE TABLE USERS (a Number, b Number) |
implicit; can also be done explicitly with db.createCollection("mycoll")
|
ALTER TABLE users ADD ... |
implicit |
INSERT INTO USERS VALUES(3,5) |
db.users.insert({a:3,b:5})
|
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:{$gt:33}})
|
SELECT * FROM users WHERE age!=33 |
db.users.find({age:{$ne: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})
|
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( { $or : [ { a : 1 } , { b : 2 } ] } )
|
SELECT * FROM users LIMIT 1 |
db.users.findOne() |
SELECT DISTINCT last_name FROM users |
db.users.distinct('last_name')
|
SELECT COUNT(*y) FROM users |
db.users.count() |
SELECT COUNT(*y) FROM users where AGE > 30 |
db.users.find({age: {'$gt': 30}}).count()
|
SELECT COUNT(AGE) from users |
db.users.find({age: {'$exists': true}}).count()
|
CREATE INDEX myindexname ON users(name) |
db.users.ensureIndex({name:1})
|
CREATE INDEX myindexname ON users(name,ts DESC) |
db.users.ensureIndex({name:1,ts:-1})
|
EXPLAIN SELECT * FROM users WHERE z=3 |
db.users.find({z:3}).explain()
|
UPDATE users SET a=1 WHERE b='q' |
db.users.update({b:'q'}, {$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'});
|