Pass through mappings are used in Informatica to insert all source rows into target in situations where we don’t have to keep the history of data. For example if you take the case Invoice table, at the end of the year we will have new invoices, hence we need to drop the existing dimension and reload the entire table. We use TYPE 1 Dimension Mapping preferably for records which change incrementally.
A single pass through mapping will have source definition. Source qualifier, and an Expression Transformation, and target table. While customizing the mapping we can add other transformations also.
Now let’s see how to create a Pass through Mapping
- Click Mapping Wizards and in that select for Simple Pass Through.
- Give mapping name m_Mapping.
- Select source definition name
- Enter the mapping target table T_TargetName
Overall we can say that pass through mapping performs following tasks
- Select all source rows
- Insert all rows into Target