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https://issues.apache.org/jira/browse/HIVE-2029?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13133723#comment-13133723
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Ashutosh Chauhan commented on HIVE-2029:
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@Paul,
>From the url I quoted above:
bq. DataNucleus has the capability to switch to between DataSources upon 
failure of one while obtaining a datastore connection. The failover mechanism 
is useful for applications with multiple database nodes when the data is 
actually replicated/synchronized by the underlying database.
So, DN will try to connect to a slave automatically when it can't connect with 
master. But it won't promote the slave to master so metastore can proceed with 
read only queries on DB. This falls short of what you have described, but once 
we upgrade to 3.x via HIVE-2084 we can atleast simplify the reconnect logic.
                
> MetaStore ConnectionURL updates need to trigger creation of Default DB if it 
> doesn't exist
> ------------------------------------------------------------------------------------------
>
>                 Key: HIVE-2029
>                 URL: https://issues.apache.org/jira/browse/HIVE-2029
>             Project: Hive
>          Issue Type: Bug
>          Components: Metastore
>    Affects Versions: 0.7.0
>            Reporter: Carl Steinbach
>         Attachments: hive_2029.patch
>
>
> HIVE-1219 defined the JDOConnectionURLHook plugin, and integrated this 
> feature into HiveMetaStore. On MetaStore operation failures, this plugin is 
> used to update the metastore ConnectionURL configuration property. Currently 
> this update triggers the reinitialization of the underlying JDO 
> PersistenceManager, but it does not trigger checks to see if the default 
> database exists, nor will it create the default database if it does not 
> exist. It needs to do both.
> This ticket also covers removing the 'hive.metastore.force.reload.conf' 
> property from HiveConf and HiveMetaStore. This property should not have been 
> added in the first place since its sole purpose is to facilitate testing of 
> the JDOConnectionURLHook mechanism by unnaturally forcing reinitialization of 
> the PersistenceManager.

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