TSDIFF
Returns NULL if any of the arguments is null.
Otherwise returns the difference between the two timestamps in milliseconds.
Syntax
TSDIFF(startTime, endTime)
Parameters
startTime
A Unix timestamp in the format milliseconds since '1970-01-01 00:00:00' UTC, expressed as a BIGINT.
endTime
A Unix timestamp in the format milliseconds since '1970-01-01 00:00:00' UTC, expressed as a BIGINT.