How to access the internal hidden columns of table by spark jdbc

I want to use spark jdbc to access alibaba cloud hologres (https://www.alibabacloud.com/product/hologres) internal hidden column `hg_binlog_timestamp_us ` but met the following error: Exception in thread "main" org.apache.spark.sql.AnalysisException: cannot resolve 'hg_binlog_timestamp_us'

How to get db related metrics when use spark jdbc to read db table?

Hello, I have a spark application with jdbc source and do some calculation. To monitor application healthy, I need db related metrics per database like number of connections, sql execution time and sql fired time distribution etc. Does anybody know how to get them? Thanks!