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https://issues.apache.org/jira/browse/HIVE-3386?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13436660#comment-13436660
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Lefty Leverenz commented on HIVE-3386:
--------------------------------------

I added the new section verbatim to [Data 
Types|https://cwiki.apache.org/confluence/display/Hive/LanguageManual+Types] in 
the wiki but wonder why you used initial capitals for Text Format.

Does this information also belong in "Inserting data into Hive Tables from 
queries" in 
[DML|https://cwiki.apache.org/confluence/display/Hive/LanguageManual+DML] as 
another bullet item in the Notes?  Or should a note just refer to the Types doc 
"for information about types and NULL values"?

Does the information also belong in the DDL docs?  Wikidoc 
[DDL|https://cwiki.apache.org/confluence/display/Hive/LanguageManual+DDL] 
already points to Types from its "Create Table" section, but in the Hive xdocs 
there's another DDL doc (misnamed 
[DML|http://hive.apache.org/docs/r0.9.0/language_manual/data-manipulation-statements.html])
 that could include this information in its "Using SerDes" section or just 
point to the Types wikidoc.
                
> Document how to import NULL values into a table at LanguageManual+Types (\N 
> with Lazy SerDe)
> --------------------------------------------------------------------------------------------
>
>                 Key: HIVE-3386
>                 URL: https://issues.apache.org/jira/browse/HIVE-3386
>             Project: Hive
>          Issue Type: Improvement
>          Components: Documentation
>    Affects Versions: 0.9.0
>            Reporter: Jakub Holy
>            Assignee: Lefty Leverenz
>
> The documentation at 
> https://cwiki.apache.org/confluence/display/Hive/LanguageManual+Types should 
> be enhanced as follows:
> ---
> Handling of NULL values
> Missing values are represented by the special value NULL. To import data with 
> NULL fields, check documentation of the SerDe used by the table. (The default 
> Text Format uses LazySimpleSerDe which interprets the string \N as NULL when 
> importing.)
> ---
> Reason:
> It's nearly impossible to find out how to make e.g. a string field to be NULL 
> in hive without lot of googling. This is an important thing and should be 
> documented properly at a clearly visible place (the Data Types page seems to 
> be the most logical place to me though LanguageManual+DML would certainly 
> also be a good place).

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