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https://issues.apache.org/jira/browse/TAJO-1856?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15027974#comment-15027974
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ASF GitHub Bot commented on TAJO-1856:
--------------------------------------
Github user jihoonson commented on a diff in the pull request:
https://github.com/apache/tajo/pull/878#discussion_r45937207
--- Diff: tajo-docs/src/main/sphinx/table_management/tablespaces.rst ---
@@ -1,9 +1,26 @@
-*************************************
+***********
Tablespaces
-*************************************
+***********
-Tablespaces in Tajo allow users to define locations in the storage system
where the files or data objects representing database objects can be stored.
Once defined, a tablespace can be referred to by name when creating a database
or a table. Especially, it is very useful when a Tajo cluster instance should
use heterogeneous storage systems such as HDFS, MySQL, and Oracle.
+Tablespaces in Tajo allow users to define locations in the storage system
where the files or data objects representing database objects can be stored.
+Once defined, a tablespace can be referred to by name when creating a
database or a table.
+Especially, it is very useful when a Tajo cluster instance should use
heterogeneous storage systems such as HDFS, MySQL, and Oracle.
+============================================
+External Table, Managed Table and Tablespace
+============================================
+
+Tajo has two types of table. One is external table. It needs **location**
property when the table is created. Using this property, you can create an
external table indicating existing external data source.
+For example, if there is already your data as Text/JSON files or HBase
table, you can register it as tajo external table.
+Other one is managed table, which means internal table, that is created in
Tajo internal table space. You can convert external data to the form that you
want and save it in managed table.
+
+Tablespace is used for managed tables and it is a kind of alias represents
physical(distributed, usually) storages. When managed table is created, you can
specify a tablespace with **tablespace** keyword, or default tablespace will be
used.
--- End diff --
I suggest ```Tablespace is a predefined physical location where data stored
on. It is supported for only managed tables. When you create a managed table,
you can use the **tablespace** keyword to specify the location of data will be
stored. If the tablespace is not specified, the default tablespace of the
table's database is used.```
> Add a description about the relationship of tablespace, managed table, and
> external table to Tablespace section of Table Management chapter
> -------------------------------------------------------------------------------------------------------------------------------------------
>
> Key: TAJO-1856
> URL: https://issues.apache.org/jira/browse/TAJO-1856
> Project: Tajo
> Issue Type: Sub-task
> Components: Documentation
> Reporter: Jihoon Son
> Assignee: Jongyoung Park
> Fix For: 0.11.1
>
>
> See the title.
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