Ray >and I thought CBO computations included fractions ... isn't that >floating point arithmatic? Of course there are lot of floating point computations. But, as I understand, the OP was interested in floating point computations that are performed directly by the CPU (otherwise, IMHO, the question makes no sense...). Since the internal format of the NUMBER datatype (and all others based on it) is oracle specific, either: 1) they implemented it without taking advantage of the capabilities of the CPU, i.e. they have a library that is platform independent doing such computations or 2) they convert the NUMBER values to CPU-dependent floating point numbers (probably IEEE 754 conform) before sending them to the CPU As of 10g through BINARY_FLOAT and BINARY_DOUBLE they support IEEE 754 numbers. With them is highly probable that the floating point computations are directly performed by the CPU. For this reason, in 10g, computations done on BINARY_FLOAT and BINARY_DOUBLE values are much faster than the same computations done on NUMBER values. Regards, Chris -- //www.freelists.org/webpage/oracle-l