What's New > Changed Behavior > Mappings
  

Mappings

Effective in the Spring 2017 release, when you select the Data Driven option for a relational target in a mapping, the update strategy expression is optional.
If you select the Data Driven option but do not configure an update strategy expression, the target uses one of the following update strategies:
Previously, when you selected the Data Driven option, the update strategy expression was required.