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README.md

 # Code samples for Data Stream Processing
 
-## Install dependencies
+## Preparation: Install dependencies
 
 ```
 pip3 -r requirements.txt
 ```
 
-## Run the Spark application
+## Word counts
 
+Start the Spark application:
+```sh
+python3 wordcount.py
 ```
-python3 average.py
+
+In another terminal session, execute
+```sh
+touch text-data/data.txt
 ```
 
-## Feed the example data into the application
+## Averages
 
+Start the Spark application:
+```sh
+python3 average.py
 ```
+
+In another terminal session, execute
+```sh
 ./send-data.sh
 ```
+
+## Averages (SQL)
+
+Start the Spark application:
+```sh
+python3 average-sql.py
+```