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module Shell
  module Commands
    class ClearBlockCache < Command
      def help
        <<-EOF
Clear all the blocks corresponding to this table from BlockCache. For expert-admins.
Calling this API will drop all the cached blocks specific to a table from BlockCache.
This can significantly impact the query performance as the subsequent queries will
have to retrieve the blocks from underlying filesystem.
For example:

  hbase> clear_block_cache 'TABLENAME'
EOF
      end

      def command(table_name)
        formatter.row([admin.clear_block_cache(table_name)])
      end
    end
  end
end
