the problem is that the column "totmiles" in table riskfactor is of type BIGINT while the input for it coming from the "drivermileage" table is of type DOUBLE. So you either have to change the type of the "totmiles" column in "drivermileage" or in "riskfactor". Another option might be a simple cast from DOUBLE to BIGINT. I just recreated the "riskfactor" table using DOUBLE as type for "totmileage" ... View more