Github user eminency commented on a diff in the pull request:
https://github.com/apache/tajo/pull/677#discussion_r37380325
--- Diff: tajo-docs/src/main/sphinx/partitioning/define_partition_table.rst
---
@@ -0,0 +1,73 @@
+*********************************
+Define Partition Table
+*********************************
+
+Tajo makes it easy to specify an automatic partition scheme when the table
is created.
+
+================================================
+How to Create Partitione Table
+================================================
+
+You can create a partitioned table by using the ``PARTITION BY`` clause.
For a column partitioned table, you should use
+the ``PARTITION BY COLUMN`` clause with partition keys.
+
+For example, assume there is a table ``student`` composed of the following
schema.
+
+.. code-block:: sql
+
+ id INT,
+ name TEXT,
+ grade TEXT
+
+Now you want to partition on country. Your Tajo definition would be this:
+
+.. code-block:: sql
+
+ CREATE TABLE student (
+ id INT,
+ name TEXT,
+ grade TEXT
+ ) PARTITION BY COLUMN (country TEXT);
+
+Now your users will still query on ``WHERE country = '...'`` but the 2nd
column will be the original values.
+Here's an example statement to create a table:
+
+.. code-block:: sql
+
+ CREATE TABLE student (
+ id INT,
+ name TEXT,
+ grade TEXT
+ ) USING PARQUET
+ PARTITION BY COLUMN (country TEXT, city TEXT);
+
+The statement above creates the student table with id, name, grade. The
table is also partitioned and data is stored in parquet files.
+
+You might have noticed that while the partitioning key columns are a part
of the table DDL, theyâre only listed in the ``PARTITION BY`` clause. In
Tajo, as data is written to disk, each partition of data will be automatically
split out into different folders, e.g. country=USA/city=NEWYORK. During a read
operation, Tajo will use the folder structure to quickly locate the right
partitions and also return the partitioning columns as columns in the result
set.
+
+
+==================================================
+Partition Pruning on Partition Table
+==================================================
+
+The following predicates in the ``WHERE`` clause can be used to prune
unqualified column partitions without processing
+during query planning phase.
+
+* ``=``
+* ``<>``
+* ``>``
+* ``<``
+* ``>=``
+* ``<=``
+* LIKE predicates with a leading wild-card character
+* IN list predicates
+
+Now above example table data is partitioned by country and city, so when
the query is applied on table it can easily access the required row by the help
partitions
--- End diff --
'the help of partitions' looks better
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