I am going to go through some of the settings within Oracle Warehouse Builder. First, I go through the Runtime Parameters. If you right-click on a mapping and hit "configure" you can expand a list of options. One of the is Runtime Parameters.
Default Operating Mode
Using Row Based will be slooooow. Why? Because you are using cursors, and so, it is like a for loop so, it is essentially
for a in <select> ...update or insert
This is good if you want to see the warnings/errors to know why set based is not loading.
Set based mode is basically putting your mapping into one ginormous sql statement. This is fast. Why is it fast? I am glad you asked. Because, as the name implies, you are using a set of data, not a row of data. Once the data loads, since its in one big chunck, it will appear in the target tables all at once. You won't use the added layer of PLSQL. The drawback is say you have a Foreign Key constraint violation. In row based it would roll back that record and continue. In set based it will roll the WHOLE thing back and no data would be loaded and you would be confused. You can combine these two with Set Based with row based as fail over. So, if the set based fails, it will go into row based.
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