Hello all, I want to implement difference operator by using MapReduce. I read two tables by using MultiTableInputFormat. In the Map phase, I need to tag the name of table into each row, but how can I get the table name?
One way I can think is to create HTable instance for each table in the setup() function. And in the map function, call get method to check if the input row is belonged to table_1 or table_2. However, this approach is slow. Can someone share some different ideas? regards! Yong
