Returns the ISO DateTime value (UTC time zone) when the function is called for each individual record. Thus, over the course of the job runtime the records ClockTime will progress. This differs from CurrentTime() where the DateTime value returned is for when the job was submitted and thus all the records have the same CurrentTime.
ClockTime() returns current time (Eg: 2018-09-30T16:38:45.979Z ).
Return value datatype