Order based Transportation requests (OTR) and delivery based transport requests (DTR) are required in standalone version of TM required to replicate Sales/Purchase/Stock Transfer Order /Delivery data into the TM instance.
When TM runs as part of S/4 (which is possible since S/4 1709) no OTR/DTR is required, we have direct access to the underlying objects and replicating them would be a waste.
However, you might want to access similar structures in conditions, e.g. for the freight unit building rule determination. Hmh, sounds a bit complicated. But basically it´s simple, just add the magic class /SCMTMS/CL_COND_TRQ_CT_EXTR or better /SCMTMS/CL_COND_TRQTR_EXTR to your data access definition at the data is available.
A data access definition accessing the "TRQ" item product could e.g. look like this:
What´s the magic behind?
We are still mapping the different S/4 objects like Sales Orders etc. into one normalized format, which has the same structure like the TRQ, but this is done only during runtime, it is not stored on database. This data access class accesses the node data in this transient TRQ (we call it tTRQ internally) and provides it the way you are used to when accessing the normal TRQ. Full data crawler access is not possible, since there is no real BO instance.