how to hint cardinality of JdbcTable

[Константин Новиков <ko...@mail.ru.INVALID>]

Hi,
 
I’m providing some cardinality estimates for JDBC tables. From the API, I can easily implement a metadata handler for RowCount. But I’m encountering the following exception:
 
RelSubset [rel#32:RelSubset#0.ENUMERABLE] has wrong best cost {5.999990709E8 rows, 5.999990719E8 cpu, 0.0 io}. Correct cost is {110.0 rows, 111.0 cpu, 0.0 io}
 
I’m assuming this is because the underlying RelOptTable has a default rowCount of 100. Must I override this? Is it required to inherit JdbcTable to override getStatistic() (and thus a custom JdbcSchema implementation to create these instances)?
 
Thanks!