You can create SQL commands for Hive targets. You can execute the SQL commands to execute SQL statements such as insert, update, and delete on the Hive target.
PreSQL is an SQL command that runs against the Hive target before the mapping reads from the source. PostSQL is an SQL command that runs against the Hive target after the mapping writes to the target.
You can use PreSQL and PostSQL on the Spark engine. The Data Integration Service does not validate PreSQL or PostSQL commands for a Hive target.
Pre-Mapping SQL Commands
PreSQL is an SQL command that runs against a Hive target before the mapping reads from a source.
For example, you might use a Hive target in a mapping. The data stored in the Hive target contains old records from the previous day and you must delete the old records in the Hive target before you run the mapping that writes new records to the target. To delete the old records in the Hive target, you can configure a PreSQL command.
Post-Mapping SQL Commands
PostSQL is an SQL command that runs against a Hive source after the mapping writes to the target.
For example, you might use a Hive target in a mapping that runs in a test environment. After the mapping writes to the target, you might want to delete the records stored in the Hive target so that you can test the same Hive target again in the next mapping run. To delete the records in the Hive target, you can configure a PostSQL command.
