Note that SysTime has a precision in hnsecs and PG TimeStamp in usecs.
It means that PG value will have 10 times lower precision.
And as both types are using long for internal storage it also means that PG TimeStamp can store greater range of values than SysTime.
Because of these differences, it can happen that database value will not fit to the SysTime range of values.
Returns value timestamp with time zone as SysTime
Note that SysTime has a precision in hnsecs and PG TimeStamp in usecs. It means that PG value will have 10 times lower precision. And as both types are using long for internal storage it also means that PG TimeStamp can store greater range of values than SysTime.
Because of these differences, it can happen that database value will not fit to the SysTime range of values.