minor, generate item_count value for sample data
minor, generate item_count value for sample data

Signed-off-by: Hongbin Ma <85dffadbcf9f62fac2ae7c1cb8fa535b9035a526@apache.org>

apache/kylin,apache/incubator-kylin,apache/kylin,apache/incubator-kylin,apache/kylin,apache/kylin,apache/incubator-kylin,apache/incubator-kylin,apache/kylin,apache/incubator-kylin,apache/kylin,apache/incubator-kylin,apache/kylin