Informatica 9.6 How to query mapping ports from source to target?

I have a basic mapping:

• one relational source and one flat file source
• a joiner transformation
• an expression transformation
• finally the target table

I know it is possible to somehow query the metadata, but I do not know how or what tool to use.

How can I get a list of all starting source columns(output ports at source) linked to their final target column(input ports at target)?

Having the intermediate steps (example, source to joiner, joiner to expression, expression to target), would be very helpful as well, but source to target is the most important.

Querying metadata is not very convenient. You can try to export your mapping to XML and use http://powercenter-xmlanalyzer.appspot.com/ to do the source-to-target dependency analysis for you.