Introduction to Document Databases with RavenDB

David Green@davidjeet

Agenda NoSql databases Prereqs CAP Theory Features of Document Databases Features of RavenDB Getting Started – Deployment Raven Studio Code Demo 1 – CRUD + Http API Code Demo 2 – MVC3 Template, Indexes, Map-Reduce,

Lucene, Http API Extras

Pre-Reqs: What you need to know

• .NET Framework, C# 3.5/4.0

• Basic familiarity with LINQ & lambda expressions

• Maybe some JavaScript (if you want to use HTTP API)

NoSQL databases

Graph Key-value store

Object Document

Document databases• Key/Value: A document database is, at its core, a key/value

store with one major exception.

• Format: Instead of just storing any blob in it, a document db requires that the data will be store in a format that the database can understand (XML, JSON, Binary JSON, etc.)

• Schema Free: A document database is schema free, that is, you don’t have to define your schema ahead of time and adhere to that.

• Relationships Not Enforced: It does not, however, support relations. Each document is standalone. There is nothing to enforce relational integrity.

• Benefit: The major benefit of using a document database comes from the fact that while it has all the benefits of a key/value store, you aren’t limited to just querying by key.Excerpts from: http://ayende.com/blog/4459/that-no-sql-thing-document-databases

CAP Theory

Id Title Author Price33 “War & Peace” “Leo Tolstoy” 29.99

Books/33

Id Title Author417 “Pro ASP.NET MVC 4” Adam

Freeman

Books/417

Id Title Price Inventory

59 “Poke the Box”

7.18 100

Books/59

Example of a schema-less table

RavenDB• RavenDB is a document database system

• Created by Oren Eini (Ayende Rahein)

• Beyond just being your typical database, it is also a web server.

• Uses LINQ for querying (i.e. Map-Reduce).

• Uses Lucene search engine.

• Supported in MVC4, WebForms, Winforms, Console…everything

• RavenDB is optimized for reading. (some Document databases optimized for write)

• Adheres to some BASE principles:

• Basic Availability• Soft-state• Eventual consistency

Getting Started - DeploymentRaven DB has four different methods for deployment:

1. Server mode (console, not to be used in production)

2. IIS

3. Windows service

4. Embedded

Getting Started - Server Mode1. Create (or use an existing) a new solution + project

that will be using RavenDB. It doesn’t matter what kind of project this is (i.e. console, WinForms, ASP.NET, etc.)

2. With NuGet package manager, search on “RavenDB” and you can select from:

1. Raven (Embedded)2. Raven (Client)3. Raven (Server)Select the third option “Raven” which will install the server piece in the packages folder of your solution.

Getting Started - Server Mode

Raven Studio (like SSMS)http://localhost:8080/raven/studio.html

It’s Silverlight based (make sure you have Silverlight installed)

It *sometimes* auto-launches when firing up the console:

1. In Solution Explorer, right-clickOpen File In Windows Explorer

2. Navigate to packages/RavenDB.x.y.zzz/server

3. Create a .cmd file (notepad) with the following line:start Raven.Server.exe --debug –browser

4. Use the .cmd file you just created to launch the console (it will also launch the browser)

Basic CRUD Demo – Music Store• Read (w/o model)

• Read (basic)

• Read (dynamic index)

• Create

• Update

• Delete

Set “Target Framework” for Console Apps

Advanced Demo – StackExchange• Using a Base Controller (MVC3)

• Handling Joins

• Map-Reduce

• Indexes

• Lucene Search Engine

• Http API

Relational View of StackExchange

MVC3 Template for RavenDB usage

• Can use Singleton Design pattern or Dependency Injection.

• Using a base class for the controller (i.e. “RavenController”)

• Overriding the OnActionExecuting and OnActionExecuted event.

How to Handle Relationships in RavenDB

Couple of ways to do this:

• One common technique is to use .Include<T>() method.

• Depending on the scenario, de-normalization can be used instead.

IndexesTwo types of Indexes in RavenDB:

• Static

• Dynamic

There are a few reasons why to prefer static indexes over dynamically created ones:

High latency - Index creation is not a cheap process, and may take a while to execute. Since dynamic indexes are created on the fly on first user query, first non-stale results may take a long time to return. Since dynamic indexes are created as temporary indexes, this is going to be a performance issue on first run.

Flexibility - Static indexes expose much more functionality, like custom sorting, boosting, Full Text Search, Live Projections, spatial search support, and more.

Map- Reduce

from post in docs.Postsfrom Tag in post.Tagsselect new { Tag, Count = 1 }

from result in resultsgroup result by result.Tag into gselect new{

Tag = g.Key,Count =

(int)g.Sum(x=>x.Count)}

Example: Creating an index called Posts/TagCount

Reduce

Map

Lucene

Examples:

With “Posts” Collection:• (PostTypeId: 1 AND Title: *relativity*) • (PostTypeId: 1 AND AnswerCount: 6)• Title: “particle energy"~4 //proximity search example

With “Users” Collection:• DisplayName: David~0.4 // fuzzy search example• DisplayName: David~0.8

Syntax: http://www.lucenetutorial.com/lucene-query-syntax.html

Extras• Additional Resources

• Deleted Scenes

• Behind the camera with David Green

RavenDB Deployment – Embedded Mode

Helpful Tools• Couple tools out there – Some are RavenDB specific, others like Fiddler and LinqPad also work well.

• For setup/install:• http://

blogs.hibernatingrhinos.com/5/ravendb-in-practice-part-1-an-introduction-to-ravendb

• http://ravendb.net/docs/intro/quickstart/adding-ravendb-to-your-application• http://www.codecapers.com/post/Using-RavenDB-with-ASPNET-MVC.aspx• http://msdn.microsoft.com/en-us/magazine/hh547101.aspx

• Best Intro:• http://ravendb.net/docs/client-api• http://ravendb.net/docs/http-api• http://ravendb.net/docs/server/deployment• http://ravendb.net/kb/3/using-ravendb-in-an-asp-net-mvc-website• http://

blogs.hibernatingrhinos.com/3073/ravendb-in-practice-part-2-using-the-client-api

• http://www.codeproject.com/Articles/74322/RavenDB-An-Introduction• http://www.codecapers.com/post/Using-RavenDB-with-ASPNET-MVC.aspx• http://

tech-rash.blogspot.com/2012/02/is-raven-db-all-its-cracked-up-to-be.html (review)

• Relations/joins: • http://daniellang.net/how-to-handle-relations-in-ravendb/• http://old.ravendb.net/faq/includes

Helpful Links

Resources

MongoDB vs. CouchDB vs. RavenDBTaken from:

http://weblogs.asp.net/britchie/archive/2010/08/17/document-databases-compared-mongodb-couchdb-and-ravendb.aspx

Pricing/features for RavenDB 1.2RavenDB is being split into three editions:

RavenDB Basic - monthly subscription only (5$ - 512 MB db size limit, 5 databases limit. 10$ - 1GB db size limit, 10 databases limit). A single indexing thread, 2 GB memory limit. 

RavenDB Standard - what we have with RavenDB right now. 6 CPU + 12 GB limit. 999$ for a one time payment - 18 months upgrade protection.  399$ for a yearly subscription - as long as you have a current subscription, you can use the software and get free upgrades. 39$ for a monthly subscription 

RavenDB Enterprise - per core licensing. No limits on CPU / Mem. Additional features, detailed in the previous email.  Per core pricing (# of cores == Environment.ProcessCount) is 699$ per core . 18 months upgrade protection.  299$ per core per year. 79$ per core per quarter 

In addition to that we have two additional licensing modes:1) OEM - embedded only - 1599$ per developer for the first year.  999$ per developer for renewal. 2) Scaleout - bundles of 10, 20 and 50 licenses for scaleout / sharding  scenarios, which are sold at a reduced cost. 

Development will continue to be free! (emphasis added).