You can choose how Data Integration handles changes that you make to the data object schemas. To refresh the schema every time the mapping task runs, you can enable dynamic schema handling in the task.
A schema change includes one or more of the following changes to the data object:
•Fields added.
•Fields updated for data type, precision, or scale.
Configure schema change handling on the Runtime Options page when you configure the task.
The following table describes the schema change handling options:
Option
Description
Asynchronous
Default. Data Integration refreshes the schema when you edit the mapping or mapping task, and when Informatica Intelligent Cloud Services is upgraded.
Dynamic
Data Integration refreshes the schema every time the task runs.
You can choose from the following options to refresh the schema:
- Alter and Apply changes. Alters the target schema and adds the new fields from the source.
- Don't Apply DDL Changes. Does not apply the schema changes to the target.
- Drop Current and Recreate. Drops the existing target table and then recreates the target table at runtime using all the incoming metadata fields from the source.
For more information, see the "Schema change handling" topic in Tasks.
Rules and guidelines for dynamic schema handling in mappings
Consider the following rules and guidelines when you enable dynamic schema change handling for tasks:
•You must use an existing target in the Target transformation to write the data.
•You can't rename the column in the target.
•When you use an exiting target table to write the data and delete a column from the source table, the deleted column still appears in the target table even though you run the task.
•You can't enable the Alter and Apply changes option for the task when you change any constraint such as primary key, not null, or unique key in the source schema.