Number of mappers for import all tables


#1

Suppose if we have been asked to import all tables . How many mappers should be used while appearing for CCA 175?
Also I have seen in some problems in spark. People use repartition(1) because saving. Can we do same if it is not explicitly specified in the question?


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#2

@connectsachit

The default no of mappers used in Sqoop is 4.
Unless it is mentioned, one should not change the number


#3

for import-all-tables
better to use
–num-mappers 1.

If a table doesn’t have a primary or unique key, your import stmt. will fail unless num-mappers is 1.