You can use "ALTER TABLE <table> SET tblproperties('comment'='')".In the latest Impala (not released yet), we have new COMMENT ON statements to add/remove comments: https://issues.apache.org/jira/browse/IMPALA-5614. COMMENT ON table/view changes were recently merged. To remove the a comment from a table, you can use "COMMENT ON <table> IS NULL". >
