Querying Hive table questions


Jianliang Qi
 

Hi devs.
I'm new to PrestoDB. I have a question about querying Hive tables.

When querying the hive table, the coordinator how to decide each worker to read which hdfs files? Is through the Hive partition to read or specific files?

Is the specific file information corresponding to the hive table already obtained before the task is sent to the worker or is it obtained by the worker itself after receiving the task?

I have read the code of Hive Connector. I find that `com.facebook.presto.hive.DirectoryLister#list` is to list the actual files in HDFS. But I can not tell that it is called in coordinator or worker.

Is there any information for reference?I have referred the official docs and other blogs, but have not find any information.

Looking forward to hearing from you.

Jianliang Qi