Github user hyunsik commented on a diff in the pull request:
https://github.com/apache/tajo/pull/756#discussion_r40056645
--- Diff: tajo-docs/src/main/sphinx/table_management/json.rst ---
@@ -0,0 +1,100 @@
+****
+JSON
+****
+
+JSON(JavaScript Object Notation) is an open standard format for data
(de)serialization. Since it is simple and human-readable, it is popularly used
in many fields.
+Tajo supports JSON as its data format. In this section, you will get an
overview of how to create JSON tables and query on them.
+
+============================
+How to Create a JSON Table ?
+============================
+
+You can create JSON tables using ``CREATE TABLE`` statement. (For more
information, please refer to :doc:`/sql_language/ddl`.)
+For example, please consider an example data as follows:
+
+.. code-block:: bash
+
+ $ hdfs dfs -cat /table1/table.json
+ { "title" : "Hand of the King", "name" : { "first_name": "Eddard",
"last_name": "Stark"}}
+ { "title" : "Assassin", "name" : { "first_name": "Arya", "last_name":
"Stark"}}
+ { "title" : "Dancing Master", "name" : { "first_name": "Syrio",
"last_name": "Forel"}}
+
+Tajo provides two alternatives to create a table for this data. First is a
traditional way to create tables. Here is an example.
+
+.. code-block:: sql
+
+ CREATE EXTERNAL TABLE table1 (
+ title TEXT,
+ name RECORD (
+ first_name TEXT,
+ last_name TEXT
+ )
+ ) USING JSON LOCATION '/table1/table.json';
+
+With this way, you need to specify every column which they want to use.
This will be a tedious work, and not appropriate for flexible JSON schema.
+Second is a simpler alternative to alleviate this problem. When you create
an external table of JSON format, you can simply omit the column specification
as follows:
+
+.. code-block:: sql
+
+ CREATE EXTERNAL TABLE table1 USING JSON LOCATION '/table1/table.json';
--- End diff --
It needs to reflect the changed schema description way; i.e., ``(*)``.
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