Thanks for your detailed explanations.

I'm not asking what the concepts of INTERNAL TABLE and EXTERNAL TABLE in hive, 
I'm just confused what does the value "EXTERNAL_TABLE" in class 
org.apache.hadoop.hive.TableType mean?

I create a table setting table type TableType.EXTERNAL_TABLE by calling hive 
metastore api like this:

final HiveMetaStoreClient client = new HiveMetaStoreClient(c);

Table newTable = new Table();




then I describe the created table with hive metastore api:

client.getTable("dbName", "tableName");

I can see that the table type is still "MANAGED_TABLE", is this a bug of 
metastore api?

发件人: Mich Talebzadeh <>
发送时间: 2016年12月2日 5:29
收件人: user
主题: Re: Difference between MANAGED_TABLE and EXTERNAL_TABLE in 

Adding to Alan's points external tables are used often as a staging area. For 
example, ingesting data from HDFS location on a daily basis and putting that 
data into Hive managed tables. That location of that external table can change 
pointing to a new HDFS directory created by say Flume etc through ALTER table 
like below



Dr Mich Talebzadeh



Mich Talebzadeh<>
Technical Architecture, Big Data, Oracle, Sybase, CEP, IMDB and Data Grid

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On 1 December 2016 at 17:53, Alan Gates 
<<>> wrote:
Hive does not assume that it owns the data for an external table.  Thus when an 
external table is dropped, the data is not deleted.  People often use this as a 
way to load data into a directory in HDFS and then “cast” a table structure 
over it by creating an external table with that directory as its location.


> On Dec 1, 2016, at 06:15, Huang Meilong 
> <<>> wrote:
> Hi all,
> I found an enum TableType in package org.apache.hadoop.hive.metastore. What's 
> the difference between MANAGED_TABLE and EXTERNAL_TABLE?
> Will the table be an EXTERNAL TABLE with setting table type EXTERNAL_TABLE 
> when creating table?
> I found the code to determine whether a table is an external table in 
> I'm confused what is EXTERNAL_TABLE in TableType for?

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