How to journal tables in SQL?
You may start DB2 table journaling with the QSYS2.QCMDEXC procedure and a corresponding text of the STRJRNPF CL command as an argument. Something like this:

CALL QSYS2.QCMDEXC('STRJRNPF FILE(MYFILELIB/MYFILENAME) JRN(MYLIB/USRJRN) IMAGES(*BOTH) OMTJRNE(*OPNCLO)');