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From m...@apache.org
Subject incubator-zeppelin git commit: [ZEPPELIN-382] Add Documentation for Cassandra interpreter in the doc…
Date Sun, 08 Nov 2015 00:35:58 GMT
Repository: incubator-zeppelin
Updated Branches:
  refs/heads/master cd0010d69 -> 8b7556df1


[ZEPPELIN-382] Add Documentation for Cassandra interpreter in the doc…

Linked **[JIRA]**

[JIRA]: https://issues.apache.org/jira/browse/ZEPPELIN-382?jql=project%20%3D%20ZEPPELIN

Author: DuyHai DOAN <doanduyhai@gmail.com>

Closes #384 from doanduyhai/CassandraInterpreterDocumentation and squashes the following commits:

b0bf36a [DuyHai DOAN] [ZEPPELIN-382] Add Documentation for Cassandra interpreter in the doc
pages


Project: http://git-wip-us.apache.org/repos/asf/incubator-zeppelin/repo
Commit: http://git-wip-us.apache.org/repos/asf/incubator-zeppelin/commit/8b7556df
Tree: http://git-wip-us.apache.org/repos/asf/incubator-zeppelin/tree/8b7556df
Diff: http://git-wip-us.apache.org/repos/asf/incubator-zeppelin/diff/8b7556df

Branch: refs/heads/master
Commit: 8b7556df11c732029d694bbd492b0d30865d3b0c
Parents: cd0010d
Author: DuyHai DOAN <doanduyhai@gmail.com>
Authored: Mon Nov 2 12:57:29 2015 +0100
Committer: Lee moon soo <moon@apache.org>
Committed: Sun Nov 8 09:36:05 2015 +0900

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--- a/docs/docs/index.md
+++ b/docs/docs/index.md
@@ -19,16 +19,17 @@ group: nav-right
 
 **[Interpreters in zeppelin](manual/interpreters.html)**
 
+* [cassandra](./interpreter/cassandra.html)
 * [flink](./interpreter/flink.html)
+* [geode](./interpreter/geode.html)
 * [hive](../docs/pleasecontribute.html)
 * [ignite](./interpreter/ignite.html)
 * [lens](./interpreter/lens.html)
 * [md](../docs/pleasecontribute.html)
+* [postgresql, hawq](./interpreter/postgresql.html)
 * [sh](../docs/pleasecontribute.html)
 * [spark](./interpreter/spark.html)
 * [tajo](../docs/pleasecontribute.html)
-* [postgresql, hawq](./interpreter/postgresql.html)
-* [geode](./interpreter/geode.html)
 
 ### Display System
 

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@@ -0,0 +1,807 @@
+---
+layout: page
+title: "Cassandra Interpreter"
+description: "Cassandra Interpreter"
+group: manual
+---
+{% include JB/setup %}
+
+<hr/>
+## 1. Cassandra CQL Interpreter for Apache Zeppelin
+
+<br/>
+<table class="table-configuration">
+  <tr>
+    <th>Name</th>
+    <th>Class</th>
+    <th>Description</th>
+  </tr>
+  <tr>
+    <td>%cassandra</td>
+    <td>CassandraInterpreter</td>
+    <td>Provides interpreter for Apache Cassandra CQL query language</td>
+  </tr>
+</table>
+
+<hr/>
+
+## 2. Enabling Cassandra Interpreter
+
+ In a notebook, to enable the **Cassandra** interpreter, click on the **Gear** icon and select
**Cassandra**
+ 
+ <center>
+ ![Interpreter Binding](/assets/themes/zeppelin/img/docs-img/cassandra-InterpreterBinding.png)
+ 
+ ![Interpreter Selection](/assets/themes/zeppelin/img/docs-img/cassandra-InterpreterSelection.png)
+ </center>
+
+<hr/>
+ 
+## 3. Using the Cassandra Interpreter
+
+ In a paragraph, use **_%cassandra_** to select the **Cassandra** interpreter and then input
all commands.
+ 
+ To access the interactive help, type **HELP;**
+ 
+ <center>
+  ![Interactive Help](/assets/themes/zeppelin/img/docs-img/cassandra-InteractiveHelp.png)
+ </center>
+
+<hr/>
+
+## 4. Interpreter Commands
+
+ The **Cassandra** interpreter accepts the following commands
+ 
+<center>
+  <table class="table-configuration">
+    <tr>
+      <th>Command Type</th>
+      <th>Command Name</th>
+      <th>Description</th>
+    </tr>
+    <tr>
+      <td nowrap>Help command</td>
+      <td>HELP</td>
+      <td>Display the interactive help menu</td>
+    </tr>
+    <tr>
+      <td nowrap>Schema commands</td>
+      <td>DESCRIBE KEYSPACE, DESCRIBE CLUSTER, DESCRIBE TABLES ...</td>
+      <td>Custom commands to describe the Cassandra schema</td>
+    </tr>
+    <tr>
+      <td nowrap>Option commands</td>
+      <td>@consistency, @retryPolicy, @fetchSize ...</td>
+      <td>Inject runtime options to all statements in the paragraph</td>
+    </tr>
+    <tr>
+      <td nowrap>Prepared statement commands</td>
+      <td>@prepare, @bind, @remove_prepared</td>
+      <td>Let you register a prepared command and re-use it later by injecting bound
values</td>
+    </tr>
+    <tr>
+      <td nowrap>Native CQL statements</td>
+      <td>All CQL-compatible statements (SELECT, INSERT, CREATE ...)</td>
+      <td>All CQL statements are executed directly against the Cassandra server</td>
+    </tr>
+  </table>  
+</center>
+
+<hr/>
+## 5. CQL statements
+ 
+This interpreter is compatible with any CQL statement supported by Cassandra. Ex: 
+
+```sql
+
+    INSERT INTO users(login,name) VALUES('jdoe','John DOE');
+    SELECT * FROM users WHERE login='jdoe';
+```                                
+
+Each statement should be separated by a semi-colon ( **;** ) except the special commands
below:
+
+1. @prepare
+2. @bind
+3. @remove_prepare
+4. @consistency
+5. @serialConsistency
+6. @timestamp
+7. @retryPolicy
+8. @fetchSize
+ 
+Multi-line statements as well as multiple statements on the same line are also supported
as long as they are 
+separated by a semi-colon. Ex: 
+
+```sql
+
+    USE spark_demo;
+
+    SELECT * FROM albums_by_country LIMIT 1; SELECT * FROM countries LIMIT 1;
+
+    SELECT *
+    FROM artists
+    WHERE login='jlennon';
+```
+
+Batch statements are supported and can span multiple lines, as well as DDL(CREATE/ALTER/DROP)
statements: 
+
+```sql
+
+    BEGIN BATCH
+        INSERT INTO users(login,name) VALUES('jdoe','John DOE');
+        INSERT INTO users_preferences(login,account_type) VALUES('jdoe','BASIC');
+    APPLY BATCH;
+
+    CREATE TABLE IF NOT EXISTS test(
+        key int PRIMARY KEY,
+        value text
+    );
+```
+
+CQL statements are <strong>case-insensitive</strong> (except for column names
and values). 
+This means that the following statements are equivalent and valid: 
+
+```sql
+
+    INSERT INTO users(login,name) VALUES('jdoe','John DOE');
+    Insert into users(login,name) vAlues('hsue','Helen SUE');
+```
+
+The complete list of all CQL statements and versions can be found below:
+<center>                                 
+ <table class="table-configuration">
+   <tr>
+     <th>Cassandra Version</th>
+     <th>Documentation Link</th>
+   </tr>
+   <tr>
+     <td><strong>2.2</strong></td>
+     <td>
+        <a target="_blank" 
+          href="http://docs.datastax.com/en/cql/3.3/cql/cqlIntro.html">
+          http://docs.datastax.com/en/cql/3.3/cql/cqlIntro.html
+        </a>
+     </td>
+   </tr>   
+   <tr>
+     <td><strong>2.1 & 2.0</strong></td>
+     <td>
+        <a target="_blank" 
+          href="http://docs.datastax.com/en/cql/3.1/cql/cql_intro_c.html">
+          http://docs.datastax.com/en/cql/3.1/cql/cql_intro_c.html
+        </a>
+     </td>
+   </tr>   
+   <tr>
+     <td><strong>1.2</strong></td>
+     <td>
+        <a target="_blank" 
+          href="http://docs.datastax.com/en/cql/3.0/cql/aboutCQL.html">
+          http://docs.datastax.com/en/cql/3.0/cql/aboutCQL.html
+        </a>
+     </td>
+   </tr>   
+ </table>
+</center>
+
+<hr/>
+
+## 6. Comments in statements
+
+It is possible to add comments between statements. Single line comments start with the hash
sign (#). Multi-line comments are enclosed between /** and **/. Ex: 
+
+```sql
+
+    #First comment
+    INSERT INTO users(login,name) VALUES('jdoe','John DOE');
+
+    /**
+     Multi line
+     comments
+     **/
+    Insert into users(login,name) vAlues('hsue','Helen SUE');
+```
+
+<hr/>
+
+## 7. Syntax Validation
+
+The interpreters is shipped with a built-in syntax validator. This validator only checks
for basic syntax errors. 
+All CQL-related syntax validation is delegated directly to **Cassandra** 
+
+Most of the time, syntax errors are due to **missing semi-colons** between statements or
**typo errors**.
+
+<hr/>
+                                    
+## 8. Schema commands
+
+To make schema discovery easier and more interactive, the following commands are supported:
+<center>                                 
+ <table class="table-configuration">
+   <tr>
+     <th>Command</th>
+     <th>Description</th>
+   </tr>
+   <tr>
+     <td><strong>DESCRIBE CLUSTER;</strong></td>
+     <td>Show the current cluster name and its partitioner</td>
+   </tr>   
+   <tr>
+     <td><strong>DESCRIBE KEYSPACES;</strong></td>
+     <td>List all existing keyspaces in the cluster and their configuration (replication
factor, durable write ...)</td>
+   </tr>   
+   <tr>
+     <td><strong>DESCRIBE TABLES;</strong></td>
+     <td>List all existing keyspaces in the cluster and for each, all the tables name</td>
+   </tr>   
+   <tr>
+     <td><strong>DESCRIBE TYPES;</strong></td>
+     <td>List all existing user defined types in the <strong>current (logged)
keyspace</strong></td>
+   </tr>   
+   <tr>
+     <td nowrap><strong>DESCRIBE FUNCTIONS &lt;keyspace_name&gt;;</strong></td>
+     <td>List all existing user defined functions in the given keyspace</td>
+   </tr>   
+   <tr>
+     <td nowrap><strong>DESCRIBE AGGREGATES &lt;keyspace_name&gt;;</strong></td>
+     <td>List all existing user defined aggregates in the given keyspace</td>
+   </tr>   
+   <tr>
+     <td nowrap><strong>DESCRIBE KEYSPACE &lt;keyspace_name&gt;;</strong></td>
+     <td>Describe the given keyspace configuration and all its table details (name,
columns, ...)</td>
+   </tr>   
+   <tr>
+     <td nowrap><strong>DESCRIBE TABLE (&lt;keyspace_name&gt;).&lt;table_name&gt;;</strong></td>
+     <td>
+        Describe the given table. If the keyspace is not provided, the current logged in
keyspace is used. 
+        If there is no logged in keyspace, the default system keyspace is used. 
+        If no table is found, an error message is raised
+     </td>
+   </tr>   
+   <tr>
+     <td nowrap><strong>DESCRIBE TYPE (&lt;keyspace_name&gt;).&lt;type_name&gt;;</strong></td>
+     <td>
+        Describe the given type(UDT). If the keyspace is not provided, the current logged
in keyspace is used. 
+        If there is no logged in keyspace, the default system keyspace is used. 
+        If no type is found, an error message is raised
+     </td>
+   </tr>   
+   <tr>
+     <td nowrap><strong>DESCRIBE FUNCTION (&lt;keyspace_name&gt;).&lt;function_name&gt;;</strong></td>
+     <td>Describe the given user defined function. The keyspace is optional</td>
+   </tr>   
+   <tr>
+     <td nowrap><strong>DESCRIBE AGGREGATE (&lt;keyspace_name&gt;).&lt;aggregate_name&gt;;</strong></td>
+     <td>Describe the given user defined aggregate. The keyspace is optional</td>
+   </tr>   
+ </table>
+</center>              
+                      
+The schema objects (cluster, keyspace, table, type, function and aggregate) are displayed
in a tabular format. 
+There is a drop-down menu on the top left corner to expand objects details. On the top right
menu is shown the Icon legend.
+
+<br/>
+<center>
+  ![Describe Schema](/assets/themes/zeppelin/img/docs-img/cassandra-DescribeSchema.png)
+</center>
+
+<hr/>
+
+## 9. Runtime Parameters
+
+Sometimes you want to be able to pass runtime query parameters to your statements. 
+Those parameters are not part of the CQL specs and are specific to the interpreter. 
+Below is the list of all parameters: 
+
+<br/>
+<center>                                 
+ <table class="table-configuration">
+   <tr>
+     <th>Parameter</th>
+     <th>Syntax</th>
+     <th>Description</th>
+   </tr>
+   <tr>
+     <td nowrap>Consistency Level</td>
+     <td><strong>@consistency=<em>value</em></strong></td>
+     <td>Apply the given consistency level to all queries in the paragraph</td>
+   </tr>
+   <tr>
+     <td nowrap>Serial Consistency Level</td>
+     <td><strong>@serialConsistency=<em>value</em></strong></td>
+     <td>Apply the given serial consistency level to all queries in the paragraph</td>
+   </tr>
+   <tr>
+     <td nowrap>Timestamp</td>
+     <td><strong>@timestamp=<em>long value</em></strong></td>
+     <td>
+        Apply the given timestamp to all queries in the paragraph.
+        Please note that timestamp value passed directly in CQL statement will override this
value
+      </td>
+   </tr>
+   <tr>
+     <td nowrap>Retry Policy</td>
+     <td><strong>@retryPolicy=<em>value</em></strong></td>
+     <td>Apply the given retry policy to all queries in the paragraph</td>
+   </tr>
+   <tr>
+     <td nowrap>Fetch Size</td>
+     <td><strong>@fetchSize=<em>integer value</em></strong></td>
+     <td>Apply the given fetch size to all queries in the paragraph</td>
+   </tr>
+ </table>
+</center>
+
+ Some parameters only accept restricted values: 
+
+<br/>
+<center>                                 
+ <table class="table-configuration">
+   <tr>
+     <th>Parameter</th>
+     <th>Possible Values</th>
+   </tr>
+   <tr>
+     <td nowrap>Consistency Level</td>
+     <td><strong>ALL, ANY, ONE, TWO, THREE, QUORUM, LOCAL_ONE, LOCAL_QUORUM,
EACH_QUORUM</strong></td>
+   </tr>
+   <tr>
+     <td nowrap>Serial Consistency Level</td>
+     <td><strong>SERIAL, LOCAL_SERIAL</strong></td>
+   </tr>
+   <tr>
+     <td nowrap>Timestamp</td>
+     <td>Any long value</td>
+   </tr>
+   <tr>
+     <td nowrap>Retry Policy</td>
+     <td><strong>DEFAULT, DOWNGRADING_CONSISTENCY, FALLTHROUGH, LOGGING_DEFAULT,
LOGGING_DOWNGRADING, LOGGING_FALLTHROUGH</strong></td>
+   </tr>
+   <tr>
+     <td nowrap>Fetch Size</td>
+     <td>Any integer value</td>
+   </tr>
+ </table>
+</center> 
+
+>Please note that you should **not** add semi-colon ( **;** ) at the end of each parameter
statement
+
+Some examples: 
+
+```sql
+
+    CREATE TABLE IF NOT EXISTS spark_demo.ts(
+        key int PRIMARY KEY,
+        value text
+    );
+    TRUNCATE spark_demo.ts;
+
+    # Timestamp in the past
+    @timestamp=10
+
+    # Force timestamp directly in the first insert
+    INSERT INTO spark_demo.ts(key,value) VALUES(1,'first insert') USING TIMESTAMP 100;
+
+    # Select some data to make the clock turn
+    SELECT * FROM spark_demo.albums LIMIT 100;
+
+    # Now insert using the timestamp parameter set at the beginning(10)
+    INSERT INTO spark_demo.ts(key,value) VALUES(1,'second insert');
+
+    # Check for the result. You should see 'first insert'
+    SELECT value FROM spark_demo.ts WHERE key=1;
+```
+                                
+Some remarks about query parameters:
+  
+> 1. **many** query parameters can be set in the same paragraph
+> 2. if the **same** query parameter is set many time with different values, the interpreter
only take into account the first value
+> 3. each query parameter applies to **all CQL statements** in the same paragraph, unless
you override the option using plain CQL text (like forcing timestamp with the USING clause)
+> 4. the order of each query parameter with regard to CQL statement does not matter
+
+<hr/>
+
+## 10. Support for Prepared Statements
+
+For performance reason, it is better to prepare statements before-hand and reuse them later
by providing bound values. 
+This interpreter provides 3 commands to handle prepared and bound statements: 
+
+1. **@prepare**
+2. **@bind**
+3. **@remove_prepared**
+
+Example: 
+
+```
+
+    @prepare[statement_name]=...
+
+    @bind[statement_name]=’text’, 1223, ’2015-07-30 12:00:01’, null, true, [‘list_item1’,
’list_item2’]
+
+    @bind[statement_name_with_no_bound_value]
+
+    @remove_prepare[statement_name]
+```
+
+<br/>
+#### a. @prepare
+<br/>
+You can use the syntax _"@prepare[statement_name]=SELECT ..."_ to create a prepared statement.

+The _statement_name_ is **mandatory** because the interpreter prepares the given statement
with the Java driver and 
+saves the generated prepared statement in an **internal hash map**, using the provided _statement_name_
as search key.
+  
+> Please note that this internal prepared statement map is shared with **all notebooks**
and **all paragraphs** because 
+there is only one instance of the interpreter for Cassandra
+  
+> If the interpreter encounters **many** @prepare for the **same _statement_name_ (key)**,
only the **first** statement will be taken into account.
+  
+Example: 
+
+```
+
+    @prepare[select]=SELECT * FROM spark_demo.albums LIMIT ?
+
+    @prepare[select]=SELECT * FROM spark_demo.artists LIMIT ?
+```                                
+
+For the above example, the prepared statement is _SELECT * FROM spark_demo.albums LIMIT ?_.

+_SELECT * FROM spark_demo.artists LIMIT ?_ is ignored because an entry already exists in
the prepared statements map with the key select. 
+
+In the context of **Zeppelin**, a notebook can be scheduled to be executed at regular interval,

+thus it is necessary to **avoid re-preparing many time the same statement (considered an
anti-pattern)**.
+<br/>
+<br/>
+#### b. @bind
+<br/>
+Once the statement is prepared (possibly in a separated notebook/paragraph). You can bind
values to it: 
+
+```
+    @bind[select_first]=10
+```                                
+
+Bound values are not mandatory for the **@bind** statement. However if you provide bound
values, they need to comply to some syntax:
+
+* String values should be enclosed between simple quotes ( ‘ )
+* Date values should be enclosed between simple quotes ( ‘ ) and respect the formats:
+  1. yyyy-MM-dd HH:MM:ss
+  2. yyyy-MM-dd HH:MM:ss.SSS
+* **null** is parsed as-is
+* **boolean** (true|false) are parsed as-is
+* collection values must follow the **[standard CQL syntax]**:
+  * list: [‘list_item1’, ’list_item2’, ...]
+  * set: {‘set_item1’, ‘set_item2’, …}
+  * map: {‘key1’: ‘val1’, ‘key2’: ‘val2’, …}
+* **tuple** values should be enclosed between parenthesis (see **[Tuple CQL syntax]**): (‘text’,
123, true)
+* **udt** values should be enclosed between brackets (see **[UDT CQL syntax]**): {stree_name:
‘Beverly Hills’, number: 104, zip_code: 90020, state: ‘California’, …}
+
+> It is possible to use the @bind statement inside a batch:
+> 
+> ```sql
+>  
+>     BEGIN BATCH
+>         @bind[insert_user]='jdoe','John DOE'
+>         UPDATE users SET age = 27 WHERE login='hsue';
+>     APPLY BATCH;
+> ```
+
+<br/>
+#### c. @remove_prepare
+<br/>
+To avoid for a prepared statement to stay forever in the prepared statement map, you can
use the 
+**@remove_prepare[statement_name]** syntax to remove it. 
+Removing a non-existing prepared statement yields no error.
+
+<hr/>
+
+## 11. Using Dynamic Forms
+
+Instead of hard-coding your CQL queries, it is possible to use the mustache syntax ( **\{\{
\}\}** ) to inject simple value or multiple choices forms. 
+
+The syntax for simple parameter is: **\{\{input_Label=default value\}\}**. The default value
is mandatory because the first time the paragraph is executed, 
+we launch the CQL query before rendering the form so at least one value should be provided.

+
+The syntax for multiple choices parameter is: **\{\{input_Label=value1 | value2 | … | valueN
\}\}**. By default the first choice is used for CQL query 
+the first time the paragraph is executed. 
+
+Example: 
+
+{% raw %}
+    #Secondary index on performer style
+    SELECT name, country, performer
+    FROM spark_demo.performers
+    WHERE name='{{performer=Sheryl Crow|Doof|Fanfarlo|Los Paranoia}}'
+    AND styles CONTAINS '{{style=Rock}}';
+{% endraw %}
+                                
+
+In the above example, the first CQL query will be executed for _performer='Sheryl Crow' AND
style='Rock'_. 
+For subsequent queries, you can change the value directly using the form. 
+
+> Please note that we enclosed the **\{\{ \}\}** block between simple quotes ( **'** )
because Cassandra expects a String here. 
+> We could have also use the **\{\{style='Rock'\}\}** syntax but this time, the value
displayed on the form is **_'Rock'_** and not **_Rock_**. 
+
+It is also possible to use dynamic forms for **prepared statements**: 
+
+{% raw %}
+
+    @bind[select]=='{{performer=Sheryl Crow|Doof|Fanfarlo|Los Paranoia}}', '{{style=Rock}}'
+  
+{% endraw %}
+
+<hr/>
+
+## 12. Execution parallelism and shared states
+
+It is possible to execute many paragraphs in parallel. However, at the back-end side, we’re
still using synchronous queries. 
+_Asynchronous execution_ is only possible when it is possible to return a `Future` value
in the `InterpreterResult`. 
+It may be an interesting proposal for the **Zeppelin** project.
+
+Another caveat is that the same `com.datastax.driver.core.Session` object is used for **all**
notebooks and paragraphs.
+Consequently, if you use the **USE _keyspace name_;** statement to log into a keyspace, it
will change the keyspace for
+**all current users** of the **Cassandra** interpreter because we only create 1 `com.datastax.driver.core.Session`
object
+per instance of **Cassandra** interpreter.
+
+The same remark does apply to the **prepared statement hash map**, it is shared by **all
users** using the same instance of **Cassandra** interpreter.
+
+Until **Zeppelin** offers a real multi-users separation, there is a work-around to segregate
user environment and states: 
+_create different **Cassandra** interpreter instances_
+
+For this, first go to the **Interpreter** menu and click on the **Create** button
+<br/>
+<br/>
+<center>
+  ![Create Interpreter](/assets/themes/zeppelin/img/docs-img/cassandra-NewInterpreterInstance.png)
+</center>
+ 
+In the interpreter creation form, put **cass-instance2** as **Name** and select the **cassandra**

+in the interpreter drop-down list  
+<br/>
+<br/>
+<center>
+  ![Interpreter Name](/assets/themes/zeppelin/img/docs-img/cassandra-InterpreterName.png)
+</center>                         
+
+ Click on **Save** to create the new interpreter instance. Now you should be able to see
it in the interpreter list.
+  
+<br/>
+<br/>
+<center>
+  ![Interpreter In List](/assets/themes/zeppelin/img/docs-img/cassandra-NewInterpreterInList.png)
+</center>                         
+
+Go back to your notebook and click on the **Gear** icon to configure interpreter bindings.
+You should be able to see and select the **cass-instance2** interpreter instance in the available
+interpreter list instead of the standard **cassandra** instance.
+
+<br/>
+<br/>
+<center>
+  ![Interpreter Instance Selection](/assets/themes/zeppelin/img/docs-img/cassandra-InterpreterInstanceSelection.png)
+</center> 
+
+<hr/>
+
+## 13. Interpreter Configuration
+
+To configure the **Cassandra** interpreter, go to the **Interpreter** menu and scroll down
to change the parameters.
+The **Cassandra** interpreter is using the official **[Cassandra Java Driver]** and most
of the parameters are used
+to configure the Java driver
+
+Below are the configuration parameters and their default value.
+
+
+ <table class="table-configuration">
+   <tr>
+     <th>Property Name</th>
+     <th>Description</th>
+     <th>Default Value</th>
+   </tr>
+   <tr>
+     <td>cassandra.cluster</td>
+     <td>Name of the Cassandra cluster to connect to</td>
+     <td>Test Cluster</td>
+   </tr>
+   <tr>
+     <td>cassandra.compression.protocol</td>
+     <td>On wire compression. Possible values are: NONE, SNAPPY, LZ4</td>
+     <td>NONE</td>
+   </tr>
+   <tr>
+     <td>cassandra.credentials.username</td>
+     <td>If security is enable, provide the login</td>
+     <td>none</td>
+   </tr>
+   <tr>
+     <td>cassandra.credentials.password</td>
+     <td>If security is enable, provide the password</td>
+     <td>none</td>
+   </tr>
+   <tr>
+     <td>cassandra.hosts</td>
+     <td>
+        Comma separated Cassandra hosts (DNS name or IP address).
+        <br/>
+        Ex: '192.168.0.12,node2,node3'
+      </td>
+     <td>localhost</td>
+   </tr>
+   <tr>
+     <td>cassandra.interpreter.parallelism</td>
+     <td>Number of concurrent paragraphs(queries block) that can be executed</td>
+     <td>10</td>
+   </tr>
+   <tr>
+     <td>cassandra.keyspace</td>
+     <td>
+        Default keyspace to connect to.
+        <strong>
+          It is strongly recommended to let the default value
+          and prefix the table name with the actual keyspace
+          in all of your queries
+        </strong>
+     </td>
+     <td>system</td>
+   </tr>
+   <tr>
+     <td>cassandra.load.balancing.policy</td>
+     <td>
+        Load balancing policy. Default = <em>new TokenAwarePolicy(new DCAwareRoundRobinPolicy())</em>
+        To Specify your own policy, provide the <strong>fully qualify class name (FQCN)</strong>
of your policy.
+        At runtime the interpreter will instantiate the policy using 
+        <strong>Class.forName(FQCN)</strong>
+     </td>
+     <td>DEFAULT</td>
+   </tr>
+   <tr>
+     <td>cassandra.max.schema.agreement.wait.second</td>
+     <td>Cassandra max schema agreement wait in second</td>
+     <td>10</td>
+   </tr>
+   <tr>
+     <td>cassandra.pooling.core.connection.per.host.local</td>
+     <td>Protocol V2 and below default = 2. Protocol V3 and above default = 1</td>
+     <td>2</td>
+   </tr>
+   <tr>
+     <td>cassandra.pooling.core.connection.per.host.remote</td>
+     <td>Protocol V2 and below default = 1. Protocol V3 and above default = 1</td>
+     <td>1</td>
+   </tr>
+   <tr>
+     <td>cassandra.pooling.heartbeat.interval.seconds</td>
+     <td>Cassandra pool heartbeat interval in secs</td>
+     <td>30</td>
+   </tr>
+   <tr>
+     <td>cassandra.pooling.idle.timeout.seconds</td>
+     <td>Cassandra idle time out in seconds</td>
+     <td>120</td>
+   </tr>
+   <tr>
+     <td>cassandra.pooling.max.connection.per.host.local</td>
+     <td>Protocol V2 and below default = 8. Protocol V3 and above default = 1</td>
+     <td>8</td>
+   </tr>
+   <tr>
+     <td>cassandra.pooling.max.connection.per.host.remote</td>
+     <td>Protocol V2 and below default = 2. Protocol V3 and above default = 1</td>
+     <td>2</td>
+   </tr>
+   <tr>
+     <td>cassandra.pooling.max.request.per.connection.local</td>
+     <td>Protocol V2 and below default = 128. Protocol V3 and above default = 1024</td>
+     <td>128</td>
+   </tr>
+   <tr>
+     <td>cassandra.pooling.max.request.per.connection.remote</td>
+     <td>Protocol V2 and below default = 128. Protocol V3 and above default = 256</td>
+     <td>128</td>
+   </tr>
+   <tr>
+     <td>cassandra.pooling.new.connection.threshold.local</td>
+     <td>Protocol V2 and below default = 100. Protocol V3 and above default = 800</td>
+     <td>100</td>
+   </tr>
+   <tr>
+     <td>cassandra.pooling.new.connection.threshold.remote</td>
+     <td>Protocol V2 and below default = 100. Protocol V3 and above default = 200</td>
+     <td>100</td>
+   </tr>
+   <tr>
+     <td>cassandra.pooling.pool.timeout.millisecs</td>
+     <td>Cassandra pool time out in millisecs</td>
+     <td>5000</td>
+   </tr>
+   <tr>
+     <td>cassandra.protocol.version</td>
+     <td>Cassandra binary protocol version</td>
+     <td>3</td>
+   </tr>
+   <tr>
+     <td>cassandra.query.default.consistency</td>
+     <td>
+      Cassandra query default consistency level
+      <br/>
+      Available values: ONE, TWO, THREE, QUORUM, LOCAL_ONE, LOCAL_QUORUM, EACH_QUORUM, ALL
+     </td>
+     <td>ONE</td>
+   </tr>
+   <tr>
+     <td>cassandra.query.default.fetchSize</td>
+     <td>Cassandra query default fetch size</td>
+     <td>5000</td>
+   </tr>
+   <tr>
+     <td>cassandra.query.default.serial.consistency</td>
+     <td>
+      Cassandra query default serial consistency level
+      <br/>
+      Available values: SERIAL, LOCAL_SERIAL
+     </td>
+     <td>SERIAL</td>
+   </tr>
+   <tr>
+     <td>cassandra.reconnection.policy</td>
+     <td>
+        Cassandra Reconnection Policy.
+        Default = new ExponentialReconnectionPolicy(1000, 10 * 60 * 1000)
+        To Specify your own policy, provide the <strong>fully qualify class name (FQCN)</strong>
of your policy.
+        At runtime the interpreter will instantiate the policy using 
+        <strong>Class.forName(FQCN)</strong>
+     </td>
+     <td>DEFAULT</td>
+   </tr>
+   <tr>
+     <td>cassandra.retry.policy</td>
+     <td>
+        Cassandra Retry Policy.
+        Default = DefaultRetryPolicy.INSTANCE
+        To Specify your own policy, provide the <strong>fully qualify class name (FQCN)</strong>
of your policy.
+        At runtime the interpreter will instantiate the policy using 
+        <strong>Class.forName(FQCN)</strong>
+     </td>
+     <td>DEFAULT</td>
+   </tr>
+   <tr>
+     <td>cassandra.socket.connection.timeout.millisecs</td>
+     <td>Cassandra socket default connection timeout in millisecs</td>
+     <td>500</td>
+   </tr>
+   <tr>
+     <td>cassandra.socket.read.timeout.millisecs</td>
+     <td>Cassandra socket read timeout in millisecs</td>
+     <td>12000</td>
+   </tr>
+   <tr>
+     <td>cassandra.socket.tcp.no_delay</td>
+     <td>Cassandra socket TCP no delay</td>
+     <td>true</td>
+   </tr>
+   <tr>
+     <td>cassandra.speculative.execution.policy</td>
+     <td>
+        Cassandra Speculative Execution Policy.
+        Default = NoSpeculativeExecutionPolicy.INSTANCE
+        To Specify your own policy, provide the <strong>fully qualify class name (FQCN)</strong>
of your policy.
+        At runtime the interpreter will instantiate the policy using 
+        <strong>Class.forName(FQCN)</strong>
+     </td>
+     <td>DEFAULT</td>
+   </tr>
+ </table>
+
+<hr/>
+
+## 14. Bugs & Contacts
+
+ If you encounter a bug for this interpreter, please create a **[JIRA]** ticket and ping
me on Twitter
+ at **[@doanduyhai]**
+
+
+[Cassandra Java Driver]: https://github.com/datastax/java-driver
+[standard CQL syntax]: http://docs.datastax.com/en/cql/3.1/cql/cql_using/use_collections_c.html
+[Tuple CQL syntax]: http://docs.datastax.com/en/cql/3.1/cql/cql_reference/tupleType.html
+[UDT CQL syntax]: http://docs.datastax.com/en/cql/3.1/cql/cql_using/cqlUseUDT.html
+[JIRA]: https://issues.apache.org/jira/browse/ZEPPELIN-382?jql=project%20%3D%20ZEPPELIN
+[@doanduyhai]: https://twitter.com/doanduyhai


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