This is how i infered Tpump can be used for real time data warehousing. I may be wrong though.
Lot of companies in today's world want to get data from transactional systems into data warehouse in real time or near real time basis (Like instead of loading daily once, doing hourly loads into warehouse). Tpump is a good candidate for this task. In our company we use Tpump in this manner.
I went through Tpump documentation to find about INMOD rountine. There is whole chapter on this (chpater 5: Using INMOD and Notify Exit Routines). May be you should go through too. Below is key explanation on INMOD.
An INMOD is a user-written routine used by TPump to supply or preprocess input records before they are sent to the Teradata Database. You can use an INMOD routine to supply input records or to perform preprocessing tasks on the input records before passing them to TPump. Such tasks, for example, could:
• Generate records to be passed to TPump. • Validate data records before passing them to TPump. • Read data directly from one or more database systems like IMS, Total. • Convert fields in a data record before passing it to TPump.