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From Dain Sundstrom <d...@iq80.com>
Subject Re: [jira] [Created] (ORC-120) Create a backwards compatibility mode of ignoring names for evolution
Date Tue, 13 Dec 2016 00:42:40 GMT
So, rename column is not expected to work anymore?

-dain

> On Dec 12, 2016, at 4:14 PM, Owen O'Malley <omalley@apache.org> wrote:
> 
> No, unfortunately, but it needs to be. The basic rules from
> SchemaEvolution.java look like:
> 
> structs (including the top row):
>   if field names are available (post HIVE-4243), use name matching
>   otherwise use positional matching
> 
> lists, maps, unions:
>  children must match
> 
> Many primitives can convert to each other, but this list needs to be
> cleaned up:
>  boolean, byte, short, int, long, float, double, decimal -> boolean, byte,
> short, int, long, float, double, decimal, string, char, varchar, timestamp
>  string, char, varchar -> all
>  timestamp -> boolean, byte, short, int, long, float, double, decimal,
> string, char, varchar, date
>  date -> string, char, varchar, timestamp
>  binary -> string, char, varchar, date
> 
> .. Owen
> 
> On Mon, Dec 12, 2016 at 2:55 PM, Dain Sundstrom <dain@iq80.com> wrote:
> 
>> Is "ORC's schema evolution uses the column names when they are availableā€
>> documented somewhere?
>> 
>> -dain
>> 
>>> On Dec 12, 2016, at 2:24 PM, Owen O'Malley (JIRA) <jira@apache.org>
>> wrote:
>>> 
>>> Owen O'Malley created ORC-120:
>>> ---------------------------------
>>> 
>>>            Summary: Create a backwards compatibility mode of ignoring
>> names for evolution
>>>                Key: ORC-120
>>>                URL: https://issues.apache.org/jira/browse/ORC-120
>>>            Project: Orc
>>>         Issue Type: Task
>>>           Reporter: Owen O'Malley
>>> 
>>> 
>>> ORC's schema evolution uses the column names when they are available.
>> Hive 2.1 uses a positional schema, so ORC should support a backward
>> compatibility mode for Hive users during the transition.
>>> 
>>> 
>>> 
>>> --
>>> This message was sent by Atlassian JIRA
>>> (v6.3.4#6332)
>> 
>> 


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