Running the example

Complete the following steps to run the WordCount example.

1. Compile WordCount.java and create a .jar file:

   $ export JAVA_HOME=/nz/export/ae/languages/java/java_sdk/host
   $ export MR_HOME=/nz/export/ae/products/netezza/mapreduce/current
   $ mkdir wordcount_classes
   ${JAVA_HOME}/bin/javac \
   -classpath ${MR_HOME}/mapreduce.jar \
   -d wordcount_classes \
   WordCount.java
   ${JAVA_HOME}/bin/jar -cvf wordcount.jar -C wordcount_classes/ .

2. Create a mapreduce_db database:

   CREATE DATABASE mapreduce_db;

3. Connect to mapreduce_db and seed table wordcount_input with sample data:

   CREATE TABLE wordcount_input(
   id int,
   text varchar(100)
   );
   INSERT INTO wordcount_input VALUES(1, 'Hello World Bye World');
   INSERT INTO wordcount_input VALUES(2, 'Hello mapreduce Goodbye
   mapreduce');
   INSERT INTO wordcount_input VALUES(3, 'Hello INZA');
   1. Run the application with the following command:
   ${MR_HOME}/bin/mapreduce jar wordcount.jar WordCount \
   mapreduce_db
   wordcount_input id text \
   wordcount_output word count

4. Show output table:

   $ nzsql ${DB} -c "select * from wordcount_output"
   WORD | COUNT
   -----------+-------
   Hello | 3
   INZA | 1
   World | 2
   mapreduce | 2
   Bye | 1
   Goodbye | 1
   (6 rows)