Relational targets are valid in mappings in a Hadoop environment if you use the Hive or Blaze engine. The Spark engine cannot run mappings with relational targets.
The Data Integration Service does not run pre-mapping SQL commands or post-mapping SQL commands against relational targets in a Hadoop environment. You cannot validate and run a mapping with PreSQL or PostSQL properties for a relational target in a Hadoop environment.
The Data Integration Service can use multiple partitions to write to the following relational targets:
IBM DB2
Oracle
You do not have to set maximum parallelism for the Data Integration Service to use multiple partitions in the Hadoop environment.