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I have to change the partition column name (not partition spec), I looked for the commands in hive wiki and some google pages. I can find the options for altering the partition spec,
i.e. For example
In /table/country='US' I can change US to USA, but I want to change country to continent.
I feel like the only option available for changing partition column name is dropping and re-creating the table. Is there is any other option available please help me.
Thanks in advance.
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You can use the Hive ALTER TABLE command to change the HDFS directory location of a specific partition. The below example update the state=NC partition location from the default Hive store to a custom location /data/state=NC.
You can refresh Hive metastore partition information manually or automatically. You run the MSCK (metastore consistency check) Hive command: MSCK REPAIR TABLE table_name SYNC PARTITIONS every time you need to synchronize a partition with your file system. You set up partition discovery to occur periodically.
You use the UPDATE statement to modify data already stored in an Apache Hive table. You construct an UPDATE statement using the following syntax: UPDATE tablename SET column = value [, column = value ...] [WHERE expression];
You can change column name in metadata by following: https://cwiki.apache.org/confluence/display/Hive/LanguageManual+DDL#LanguageManualDDL-ChangeColumnName/Type/Position/Comment
But as the document says, it only changes the metadata. Hive partitions are implemented as directories with the naming pattern columnName=spec. So you also need to change the names of those directories on HDFS by using "hadoop fs" command.
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