Hi Anton, a regular TableSource does not accept a predicate and return the whole table. A ProjectableTableSource is able to evaluate a predicate while scanning. TableSources that evaluate predicates while (or rather before) scanning can significantly reduce IO compared to a full scan.
Sources that could be access with a ProjectableTableSource would be a JDBC database which pushes a query to a JDBC connected database, a Parquet file, or an ORC file. Best, Fabian 2016-11-02 13:53 GMT+01:00 Anton Solovev <anton_solo...@epam.com>: > Hi folks, > > Can you explain me what ProjectableTableSource is ? > What is it being invented for? > > Best, > Anton > >
