Added counter table example mapping

Author: msmygit

src/resources/cdm.properties

@@ -74,6 +74,23 @@ spark.batchSize                                   10
 #spark.counterTable.cql
 #spark.counterTable.cql.index                      0
 
+############################### EXAMPLE MAPPING USING A DEMO counter column TABLE ###########################
+# CREATE TABLE cycling.cyclist_count (
+#     pk1 uuid,
+#     pk2 date,
+#     cc1 boolean,
+#     c1  counter,
+#     PRIMARY KEY((pk1,pk2),cc1)
+# );
+# then, our counter table mapping would look like below,
+# spark.counterTable             true
+# spark.counterTable.cql         UPDATE cycling.cyclist_count SET c1 += ? WHERE pk1 = ? AND pk2 = ? AND cc1 = ?
+# spark.counterTable.cql.index   3,0,1,2
+#
+# Remember the above count index order is based on the below column mapping ordering,
+# spark.query.origin             pk1,pk2,cc1,c
+#############################################################################################################
+
 # ENABLE ONLY IF YOU WANT TO FILTER BASED ON WRITE-TIME (values must be in microseconds)
 #spark.origin.writeTimeStampFilter                 false
 #spark.origin.minWriteTimeStampFilter              0