Sets the number of rows to be prefetched after successful call to oci_execute(). The default value for rows is 1.
Note: In PHP versions before 5.0.0 you must use ocisetprefetch() instead. This name still can be used, it was left as alias of oci_set_prefetch() for downwards compatability. This, however, is deprecated and not recommended.
Returns TRUE on success or FALSE on failure.