Before Hive version 0.13.0, Hive does not support row-level transactions. As a result, there is no way to update, insert, or delete rows of data. Hence, data overwrite can only happen on tables or partitions. This makes Hive very difficult when dealing with concurrent read/write and data-cleaning use cases.
Since Hive version 0.13.0, Hive fully supports row-level transactions by offering full Atomicity, Consistency, Isolation, and Durability (ACID) to Hive. For now, all the transactions are autocommuted and only support data in the Optimized Row Columnar (ORC) file (available since Hive 0.11.0) format and in bucketed tables.
The following configuration parameters must be set appropriately to turn on transaction support in Hive:
SET hive.support.concurrency ...