I have a table with some 1M rows, and I would like to get the partition key of each row. Using the java driver (2.1.9), I'm executing the query
select distinct key from table; The result set is paginated automatically. My C* cluster has two datacenters, and when I run this query using consistency level LOCAL_ONE, it starts returning results (page by page) as expected. But after some time, it will give a ReadTimeoutException. This happens anywhere between 30 seconds and a few minutes. The java driver's read timeout is set to 500000 ms, and the cluster's read_request_timeout_in_ms is 300000 ms. I'm wondering what is causing this timeout? What is also not clear to me is whether the driver and server timeout apply to a single page, or to the entire query? Thanks, Tom