Return-Path: 
 <dev-return-117888-apmail-hive-dev-archive=hive.apache.org@hive.apache.org>
X-Original-To: apmail-hive-dev-archive@www.apache.org
Delivered-To: apmail-hive-dev-archive@www.apache.org
Received: from mail.apache.org (hermes.apache.org [140.211.11.3])
	by minotaur.apache.org (Postfix) with SMTP id 85C9310B98
	for <apmail-hive-dev-archive@www.apache.org>;
 Wed, 10 Dec 2014 16:50:13 +0000 (UTC)
Received: (qmail 23388 invoked by uid 500); 10 Dec 2014 16:50:13 -0000
Delivered-To: apmail-hive-dev-archive@hive.apache.org
Received: (qmail 23319 invoked by uid 500); 10 Dec 2014 16:50:13 -0000
Mailing-List: contact dev-help@hive.apache.org; run by ezmlm
Precedence: bulk
List-Help: <mailto:dev-help@hive.apache.org>
List-Unsubscribe: <mailto:dev-unsubscribe@hive.apache.org>
List-Post: <mailto:dev@hive.apache.org>
List-Id: <dev.hive.apache.org>
Reply-To: dev@hive.apache.org
Delivered-To: mailing list dev@hive.apache.org
Received: (qmail 23305 invoked by uid 500); 10 Dec 2014 16:50:12 -0000
Delivered-To: apmail-hadoop-hive-dev@hadoop.apache.org
Received: (qmail 23302 invoked by uid 99); 10 Dec 2014 16:50:12 -0000
Received: from arcas.apache.org (HELO arcas.apache.org) (140.211.11.28)
    by apache.org (qpsmtpd/0.29) with ESMTP; Wed, 10 Dec 2014 16:50:12 +0000
Date: Wed, 10 Dec 2014 16:50:12 +0000 (UTC)
From: "Chaoyu Tang (JIRA)" <jira@apache.org>
To: hive-dev@hadoop.apache.org
Message-ID: <JIRA.12748584.1413464385000.121242.1418230212914@Atlassian.JIRA>
In-Reply-To: <JIRA.12748584.1413464385000@Atlassian.JIRA>
References: <JIRA.12748584.1413464385000@Atlassian.JIRA>
 <JIRA.12748584.1413464385691@arcas>
Subject: [jira] [Commented] (HIVE-8485) HMS on Oracle incompatibility
MIME-Version: 1.0
Content-Type: text/plain; charset=utf-8
Content-Transfer-Encoding: 7bit
X-JIRA-FingerPrint: 30527f35849b9dde25b450d4833f0394


    [ https://issues.apache.org/jira/browse/HIVE-8485?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14241366#comment-14241366 ] 

Chaoyu Tang commented on HIVE-8485:
-----------------------------------

Debugging into the Hive code, I did see that Hive persists the "" (empty string) but get it back null despite that datanucleus.rdbms.persistEmptyStringAsNull is set to false. The version of DN (core) Hive uses is 3.2.10, and backend Oracle DB version is Oracle Database 11g Express Edition Release 11.2.0.2.0 - 64bit Production. 
[~andy], the property did not work as expected in Hive and do you see anything I probably missed here?

 

> HMS on Oracle incompatibility
> -----------------------------
>
>                 Key: HIVE-8485
>                 URL: https://issues.apache.org/jira/browse/HIVE-8485
>             Project: Hive
>          Issue Type: Bug
>          Components: Metastore
>         Environment: Oracle as metastore DB
>            Reporter: Ryan Pridgeon
>            Assignee: Chaoyu Tang
>
> Oracle does not distinguish between empty strings and NULL,which proves problematic for DataNucleus.
> In the event a user creates a table with some property stored as an empty string the table will no longer be accessible.
> i.e. TBLPROPERTIES ('serialization.null.format'='')
> If they try to select, describe, drop, etc the client prints the following exception.
> ERROR ql.Driver: FAILED: SemanticException [Error 10001]: Table not found <table name>
> The work around for this was to go into the hive metastore on the Oracle database and replace NULL with some other string. Users could then drop the tables or alter their data to use the new null format they just set.



--
This message was sent by Atlassian JIRA
(v6.3.4#6332)