From 34c7948e8eb470fb557c40ff470142571160d1c8 Mon Sep 17 00:00:00 2001
From: Jihoon Son <jihoonson@apache.org>
Date: Wed, 16 Sep 2015 16:12:04 +0900
Subject: [PATCH] TAJO-1853

---
 .../src/main/sphinx/sql_language/ddl.rst      | 20 +++++++++++++++++--
 .../table_management/table_overview.rst       |  2 +-
 2 files changed, 19 insertions(+), 3 deletions(-)

diff --git a/tajo-docs/src/main/sphinx/sql_language/ddl.rst b/tajo-docs/src/main/sphinx/sql_language/ddl.rst
index 662ccffe50..4d2610aeb3 100644
--- a/tajo-docs/src/main/sphinx/sql_language/ddl.rst
+++ b/tajo-docs/src/main/sphinx/sql_language/ddl.rst
@@ -10,8 +10,11 @@ CREATE DATABASE
 
 .. code-block:: sql
 
-  CREATE DATABASE [IF NOT EXISTS] <database_name> 
+  CREATE DATABASE [IF NOT EXISTS] <database_name>
 
+*Description*
+
+Database is the namespace in Tajo. A database can contain multiple tables which have unique name in it.
 ``IF NOT EXISTS`` allows ``CREATE DATABASE`` statement to avoid an error which occurs when the database exists.
 
 ========================
@@ -34,12 +37,18 @@ CREATE TABLE
 
 .. code-block:: sql
 
-  CREATE TABLE [IF NOT EXISTS] <table_name> [(<column_name> <data_type>, ... )]
+  CREATE TABLE [IF NOT EXISTS] <table_name> [(<column_name> <data_type>, ... )] [TABLESPACE tablespace_name]
   [using <storage_type> [with (<key> = <value>, ...)]] [AS <select_statement>]
 
   CREATE EXTERNAL TABLE [IF NOT EXISTS] <table_name> (<column_name> <data_type>, ... )
   using <storage_type> [with (<key> = <value>, ...)] LOCATION '<path>'
 
+*Description*
+
+In Tajo, there are two types of tables, `managed table` and `external table` (For more information, please refer to :doc:`/table_management/table_overview`.)
+
+Managed tables are placed on some predefined tablespaces. The ``TABLESPACE`` clause is to specify a tablespace for this table. For more information about tablespace, please refer to :doc:`/table_management/tablespaces`. For external tables, Tajo allows arbitrary table location with the ``LOCATION`` clause.
+
 ``IF NOT EXISTS`` allows ``CREATE [EXTERNAL] TABLE`` statement to avoid an error which occurs when the table does not exist.
 
 ------------------------
@@ -75,6 +84,8 @@ If you want to add an external table that contains compressed data, you should g
 
   DROP TABLE [IF EXISTS] <table_name> [PURGE]
 
+*Description*
+
 ``IF EXISTS`` allows ``DROP DATABASE`` statement to avoid an error which occurs when the database does not exist. ``DROP TABLE`` statement removes a table from Tajo catalog, but it does not remove the contents. If ``PURGE`` option is given, ``DROP TABLE`` statement will eliminate the entry in the catalog as well as the contents.
 
 ========================
@@ -89,6 +100,11 @@ If you want to add an external table that contains compressed data, you should g
   ( { column_name | ( expression ) } [ ASC | DESC ] [ NULLS { FIRST | LAST } ] [, ...] )
   [ WHERE predicate ]
 
+*Description*
+
+Tajo supports index for fast data retrieval. Currently, index is supported for only plain ``TEXT`` formats stored on ``HDFS``.
+For more information, please refer to :doc:`/index_overview`.
+
 ------------------------
  Index method
 ------------------------
diff --git a/tajo-docs/src/main/sphinx/table_management/table_overview.rst b/tajo-docs/src/main/sphinx/table_management/table_overview.rst
index 5818106934..d030b4a442 100644
--- a/tajo-docs/src/main/sphinx/table_management/table_overview.rst
+++ b/tajo-docs/src/main/sphinx/table_management/table_overview.rst
@@ -15,7 +15,7 @@ Please refer to :doc:`/table_management/tablespaces` if you want to know more in
 Managed Table
 ================
 
-``CREATE TABLE`` statement with ``EXTERNAL`` keyword lets you create a table located in the warehouse directory specified by the configuration property ``tajo.warehouse.directory`` or ``${tajo.root}/warehouse`` by default. For example: 
+``CREATE TABLE`` statement lets you create a table located in the warehouse directory specified by the configuration property ``tajo.warehouse.directory`` or ``${tajo.root}/warehouse`` by default. For example:
 
 .. code-block:: sql