[ https://issues.apache.org/jira/browse/HIVE-3386?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13436660#comment-13436660 ]
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). -- This message is automatically generated by JIRA. If you think it was sent incorrectly, please contact your JIRA administrators: https://issues.apache.org/jira/secure/ContactAdministrators!default.jspa For more information on JIRA, see: http://www.atlassian.com/software/jira