Let us understand how to override number of mappers as part of sqoop import command.
- Default number of mappers is 4.
- We can increase or decrease based on the table size by using -m or –num-mappers
- We need to understand the effects of increasing to a very high number. It can impact the database from which we are getting the data.
Here is the example of sqoop import with number of mappers as 8.
sqoop import \ --connect "jdbc:mysql://ms.itversity.com:3306/retail_db" \ --username retail_user \ --password itversity \ --table order_items \ --warehouse-dir /user/training/sqoop_import/retail_db \ --delete-target-dir \ --num-mappers 8