From 10a96626d47be26c95f035dbc31f61f633e60018 Mon Sep 17 00:00:00 2001
From: Brian O'Neill <bone@alumni.brown.edu>
Date: Tue, 7 May 2013 16:53:12 -0400
Subject: [PATCH] Documentation for C*

---
 examples/cassandra/README.md                  | 32 +++++++++++++++++++
 examples/cassandra/query2                     | 11 -------
 .../examples/RealtimeStandaloneMain.java      | 10 +++---
 3 files changed, 37 insertions(+), 16 deletions(-)
 create mode 100644 examples/cassandra/README.md
 delete mode 100644 examples/cassandra/query2

diff --git a/examples/cassandra/README.md b/examples/cassandra/README.md
new file mode 100644
index 00000000000..8f34c805d00
--- /dev/null
+++ b/examples/cassandra/README.md
@@ -0,0 +1,32 @@
+## Introduction
+Druid can use Cassandra as a deep storage mechanism. Segments and their metadata are stored in Cassandra in two tables:
+`index_storage` and `descriptor_storage`.  Underneath the hood, the Cassandra integration leverages Astyanax.  The 
+index storage table is a [Chunked Object](https://github.com/Netflix/astyanax/wiki/Chunked-Object-Store) repository. It contains
+compressed segments for distribution to real-time and compute nodes.  Since segments can be large, the Chunked Object storage allows the integration to multi-thread 
+the write to Cassandra, and spreads the data across all the nodes in a cluster.  The descriptor storage table is a normal C* table that 
+stores the segment metadatak.  
+
+## Schema
+Below are the create statements for each:
+
+
+
+    CREATE TABLE index_storage ( key text, chunk text, value blob, PRIMARY KEY (key, chunk)) WITH COMPACT STORAGE;
+
+    CREATE TABLE descriptor_storage ( key varchar, lastModified timestamp, descriptor varchar, PRIMARY KEY (key) ) WITH COMPACT STORAGE;
+
+
+## Getting Started
+First create the schema above.  (I use a new keyspace called `druid`) 
+
+Then, add the following properties to your properties file to enable a Cassandra 
+backend.
+
+    druid.pusher.cassandra=true
+    druid.pusher.cassandra.host=localhost:9160 
+    druid.pusher.cassandra.keyspace=druid
+
+Use the `druid-development@googlegroups.com` mailing list if you have questions,
+or feel free to reach out directly: `bone@alumni.brown.edu`.
+
+
diff --git a/examples/cassandra/query2 b/examples/cassandra/query2
deleted file mode 100644
index c53a943f899..00000000000
--- a/examples/cassandra/query2
+++ /dev/null
@@ -1,11 +0,0 @@
-{
-    "queryType": "groupBy",
-    "dataSource": "appevents",
-    "granularity": "all", 
-    "dimensions": ["appid", "event"],
-    "aggregations":[
-        {"type":"count", "name":"eventcount"},
-        {"type":"doubleSum", "fieldName":"events", "name":"eventssum"}
-    ],
-    "intervals":["2012-10-01T00:00/2020-01-01T00"]
-}
diff --git a/examples/src/main/java/druid/examples/RealtimeStandaloneMain.java b/examples/src/main/java/druid/examples/RealtimeStandaloneMain.java
index 10edff548d7..4cb267f571f 100644
--- a/examples/src/main/java/druid/examples/RealtimeStandaloneMain.java
+++ b/examples/src/main/java/druid/examples/RealtimeStandaloneMain.java
@@ -45,11 +45,11 @@ public class RealtimeStandaloneMain
     );
 
     // Create dummy objects for the various interfaces that interact with the DB, ZK and deep storage
-    //rn.setSegmentPublisher(new NoopSegmentPublisher());
-    //rn.setAnnouncer(new NoopDataSegmentAnnouncer());
-    //rn.setDataSegmentPusher(new NoopDataSegmentPusher());
-    //rn.setServerView(new NoopServerView());
-    //rn.setInventoryView(new NoopInventoryView());
+    rn.setSegmentPublisher(new NoopSegmentPublisher());
+    rn.setAnnouncer(new NoopDataSegmentAnnouncer());
+    rn.setDataSegmentPusher(new NoopDataSegmentPusher());
+    rn.setServerView(new NoopServerView());
+    rn.setInventoryView(new NoopInventoryView());
     
     Runtime.getRuntime().addShutdownHook(
         new Thread(