Hadoop Beginner's Guide

Time for action – a more selective import

Let's see how this works by performing an import that is limited by a conditional expression.

1. Delete any existing employee import directory:

   $ hadoop fs -rmr employees
   

   You will receive the following response:

   Deleted hdfs://head:9000/user/hadoop/employees
   

2. Import selected columns with a predicate:

   sqoop import --connect jdbc:mysql://10.0.0.100/hadooptest 
   --username hadoopuser -P
   --table employees --columns first_name,salary
    --where "salary > 45000" 
   --hive-import --hive-table salary 
   

   You will receive the following response:

   12/05/23 15:02:03 INFO hive.HiveImport: Hive import complete.
   

3. Examine the created table:

   $ hive -e "describe salary"
   

   You will receive the following response:

   OK
   first_name  string