Informatica "treat source row as"

Question

There are three ways in which we can specify how to treat source row in informatica :

1. By specifying in the update strategy in the mapping designer.
2. By Specifying "Treat source row as" property in session property.
3. At session level in mapping tab in the target.(By selecting various check box).

Just want to know what order informatica follows.

Answer 1

This works from most general to most detailed. So first, the session property is used for all targets. If some target has it's own setting, it's applied on top. So it's the one that is effective.

If you want to use more detailed control by using Update Transformation in a mapping that sets the property for each row separately, the session property needs to be set to Data driven - this tells the Integration Service to use row-level settings. At the same time this is least effective, i.e. most time consuming. So it should not be used by default.