hive sql 13 millisecond timestamp to date

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There is a function of timestamp to date in hive sql

from_unixtime(BIGINT unixtime [, STRING format])

The unixtime in it, the input unit is seconds, which is a ten-digit BIGINT. However, the timestamps we use in practice are generally 13-bit to millisecond timestamps. If the timestamp is directly entered into the method, there will be errors.

If it is a 13-bit timestamp, you can use it like this

from_unixtime(cast(timestamp/1000 as bigint)) as xxx_time

timestamp/1000 is a double type, just cast it directly into bigint.

Of course, you can also fill in optional parameters for the date format after the method.