TIMESTAMP(a,b)

TIMESTAMP(a,b) is a function (Extraction), which creates a time stamp value consisting of a date and time value and 0 microseconds from the expressions a and b.

TIMESTAMP(a,b)
a, b	Result of TIMESTAMP(a,b) Function
TIMESTAMP(a)	a must be a time stamp value or an alphanumeric value that matches the current time stamp format. The result is this time stamp value.
TIMESTAMP(a,b)	a must be a date value and b a time value (or alphanumeric value that matches the current format for date and time values). The result is a time stamp value calculated from a date value, time value, and 0 microseconds.
a or b is a NULL value	NULL value