MongoDB IndyRB

Transcript

2. WARNING!!! When I get excited, I talk fast. Feel free to remind me to slow down.
3. FEEDBACK @jnunemaker and @mongodb
4. WHY? WHAT? HOW?
5. WHY?
6. •Scaling, schmaling •Hammer/Nail •Example (Harmony http://harmonyapp.com)
7. WHAT?
9. INTRO • Built For Speed • Document/Collection Oriented • Dynamic Queries and Indexes • Replication and Failover
10. GREAT FOR • Websites • Caching • High volume, low value • High scalability • Storage of program objects and json
11. NOT AS GREAT FOR • Highly transactional • Ad-hoc business intelligence • Problems requiring SQL
12. INSTALLATION • mkdir -p /data/db • download, unzip, mongod run • http://video.railstips.org/mongomapper-demo/
13. DATABASE • same concept as mysql • made up of collections
14. COLLECTION • Think table, but with no schema • For grouping documents into smaller query sets (speed) • Each top level entity in your app would have its own collection (users, articles, etc.) • Indexable by one or more key
15. DOCUMENT • Stored in a collection, think record or row • Can have _id key that works like primary keys in MySQL • Three options for relationships: embedded document, foreign keys, or db reference
16. QUERYING • db.collection. fi nd({‘ fi rst_name’: ‘John’}) # fi nds all Johns • db.collection. fi nd({‘ fi rst_name’: /^J/}) # regex • db.collection. fi nd_ fi rst({‘_id’:1}) # fi nds fi rst with _id of 1 • db.collection. fi nd({‘age’: {‘$gt’: 21}}) # fi nds possible drinkers • db.collection. fi nd({‘author. fi rst_name’:‘John’}) # subdocument • db.collection. fi nd({$where:‘this.age >= 6 && this.age <= 18’})
17. MORE QUERYING • $in, $nin, $all, $ne, $gt, $gte, $lt, $lte, $size, $where • : fi elds (like :select in active record) • :limit, :offset for pagination • :sort ascending or descending [[‘foo’, 1], [‘bar’, -1]] • count and group (uses map/reduce)
18. HOW?
19. HOW DO YOU USE IT WITH RUBY • mongo-ruby-driver http://github.com/mongodb/mongo-ruby- driver • active record adapter http://github.com/mongodb/ activerecord-mongo-adapter • mongorecord http://github.com/mongodb/mongo- activerecord-ruby
20. NUNEMAPPER (MONGOMAPPER) • Mongo is not MySQL • DSL for modeling domain should also teach you Mongo • It sounded fun • Major appreciation for ORM’s
21. FEATURES • Typecasting • Callbacks (ActiveSupport Callbacks) • Validations (using my fork of validatable) • Connection and database can differ per document • Create and Update with single or multiple • Delete and Destroy and _all counterparts • Find: id, ids, :all, : fi rst, :last • Associations
22. EXAMPLE class User include MongoMapper::Document key :name, String, :required => true, :length => 5..100 key :email, String, :required => true, :index => true key :age, Integer, :numeric => true key :active, Boolean, :default => true key :address, Address many :articles end class Address include MongoMapper::EmbeddedDocument key :street, String key :city, String key :state, String, :length => 2 key :zip, Integer, :numeric => true, :length => 5 end
23. RANDOM AWESOMENESS • Capped collections (think memcache, actually used for replication) • Upserts db.collection.update({‘_id’:1}, {‘$inc’:{‘views’:1}}) • Multikeys (think tagging and full text search) • GridFS and auto-sharding
24. LINKS • http://railstips.org/2009/6/3/what-if-a-key-value-store-mated-with-a-relational-database-system • http://railstips.org/2009/6/27/mongomapper-the-rad-mongo-wrapper • http://railstips.org/2009/7/23/getting-started-with-mongomapper-and-rails • http://locomotivation.squeejee.com/post/117119353/mongodb-ruby-friendly-document-storage- that-doesnt-rhyme • http://mongodb.com/ • http://10gen.com
25. John Nunemaker http://orderedlist.com http://railstips.org