BW transport error: CL_RSTRAN_STEP_ROUT

 Recently my BW transport has crashed while being imported to target system. Error message in the transport log looked like below:

An exception of type CX_SY_OPEN_SQL_DB was raised and terminated the program, Message no. PU108

Program CL_RSTRAN_STEP_ROUT===========CP, include CL_RSTRAN_STEP_ROUT===========CM003, line 24

Errors occurred during post-handling RS_AFTER_IMPORT for * L, Message no. PU133

RS_AFTER_IMPORT belongs to package RSO_TLOGO

The errors affect the following components: Message no. PU136

   BW4-ME (Metadata (Design time)), Message no. PU137

My transport contained few BW transformations but from the error log, it wasn’t obvious which TRFN the error is related to. From a keyword “CL_RSTRAN_STEP_ROUT” that popped up in the error log, I concluded that it had something to do with a routine in the TRFN. That just did not help as most of my TRFN in the transport had routines. I tried to google the keyword as well. I just ran into an old question on SAP Community network forum. It happened that I replied on that question back in 2011 – more than eleven years ago – “huh” :) In my reply to that forum question, I suggested to “try to delete whole field routine, activate transformation and create routine again”. Therefore, I did this – right, there was nothing to lose. Just this time I focused only on TRFN which had field routines not a start/end/expert ones. I just recreated a field routines by simply deleting and recreating them.

Moreover, it worked like a charm, on next import to target system I just got a warnings not an errors.