Drop table feature

The syntax you use to create the table determines the default behavior when you drop the Iceberg table from Impala.

If you use CREATE TABLE, the external.table.purge flag is set to true. When the table is dropped, the contents of the table directory (actual data) are removed.

To prevent data loss during migration of a table to Iceberg, do not drop or move the table during migration. Exception: If you set the table property 'external.table.purge'='FALSE', no data loss occurs if you drop the table.

DROP TABLE [IF EXISTS] table_name

ALTER TABLE t SET TBLPROPERTIES('external.table.purge'='true');

DROP TABLE t;