presto-main/src/main/java/io/prestosql/sql/planner/iterative/rule/PushSampleIntoTableScan.java/PushSampleIntoTableScan/PushSampleIntoTableScan
class PushSampleIntoTableScan:    public PushSampleIntoTableScan(Metadata metadata)
    {
        this.metadata = metadata;
    }