docs/src/main/sphinx/release/release-0.57.md
The DISTINCT argument qualifier for aggregation functions is now
fully supported. For example:
SELECT country, count(DISTINCT city), count(DISTINCT age)
FROM users
GROUP BY country
:::{note}
{func}approx_distinct should be used in preference to this
whenever an approximate answer is allowable as it is substantially
faster and does not have any limits on the number of distinct items it
can process. COUNT(DISTINCT ...) must transfer every item over the
network and keep each distinct item in memory.
:::
Use the hive-hadoop2 connector to read Hive data from Hadoop 2.x.
See {doc}/installation/deployment for details.
All Hive connectors support reading data from Amazon S3. This requires two additional catalog properties for the Hive connector to specify your AWS Access Key ID and Secret Access Key:
hive.s3.aws-access-key=AKIAIOSFODNN7EXAMPLE
hive.s3.aws-secret-key=wJalrXUtnFEMI/K7MDENG/bPxRfiCYEXAMPLEKEY
/client/jdbc URL.InputFormats to work by propagating
Hive serialization properties to the RecordReader.MethodHandle exception.