The transform function must take at least one parameter which must take either of two forms:
|LEFT||formatted like any of the setofdatasets. This indicates the first dataset in the setofdatasets.|
|ROWS(LEFT)||formatted like any of the setofdatasets. This indicates a record set made up of all records from any dataset in the setofdatasets that match the joincondition--this may not include all the datasets in the setofdatasets, depending on which jointype is specified.|
The format of the resulting output record set must be the same as the input datasets.