SQL to Mongo Mapping Chart

MySQL executable Oracle executable Mongo executable
mysqld
oracle
mongod
mysql
sqlplus
mongo
MySQL term Mongo term/concept
database database
table collection
index index
row BSON document
column BSON field
join embedding and linking
primary key _id field
group by aggregation

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 order_id FROM orders o, order_line_items li WHERE li.order_id=o.order_id AND li.sku=12345
db.orders.find({"items.sku":12345},{_id:1})
SELECT customer.name FROM customers,orders WHERE orders.id="q179" AND orders.custid=customer.id
var o = db.orders.findOne({_id:"q179"});
var name = db.customers.findOne({_id:o.custid})
   
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'});

More examples, specifically aggregation examples, here

See Also

Follow @mongodb

MongoDB Pittsburgh - May 15
MongoNYC - May 23
MongoDB Paris - Jun 14
MongoDB UK - Jun 20
MongoDC - June 26


Labels

cheat cheat Delete
sheet sheet Delete
cheatsheet cheatsheet Delete
quickref quickref Delete
quick quick Delete
ref ref Delete
Enter labels to add to this page:
Please wait 
Looking for a label? Just start typing.

PLEASE POST QUESTIONS IN THE USER GROUPS FORUM. Post non-question comments and helpful hints here.

blog comments powered by Disqus