You should be able to configure the number of partition like this:
https://github.com/GoogleCloudPlatform/dataflow-cookbook/blob/main/Java/src/main/java/jdbc/ReadPartitionsJdbc.java#L132
The code to auto infer the number of partitions seems to be unreachable (I
haven't checked this carefully).
Hi Beam Experts,I have a small query about `JdbcIO#readWithPartitions`
ContextJdbcIO#readWithPartitions seems to always default to 200 partitions
(DEFAULT_NUM_PARTITIONS). This is set by default when the object is
constructed here
