After having done some researches on the topic, I have found that SQLCommit() is used occasionnaly. So, the question I have is do I really need to issue SQLCommit() to have my data to be save immediately on disk when using the ODBC approach? Usually, I only do this:

This.nHandle=SQLStringConnect(This.cSQLStringConnect)
lnResult=SQLExec(This.nHandle,'UPDATE Member SET Rank=1 WHERE Numero=1')

The process works. The data is saved on disk but it is not instantly. Under my WWC setup, so far, I was using SYS(1104) to force the data to be written to disk immediately. Working with local data, this has always worked ok for me. But, since I changed to SPT, the data is not saved immediately on disk. SYS(1104) doesn't seem to have any effect with SPT. So, is SQLCommit() the solution here or there is something better?