Gokhan Atil's Technology Blog

Sample AWS Lambda Function to Monitor Oracle Databases

I wrote a simple AWS Lambda function to demonstrate how to connect an Oracle database, gather the tablespace usage information, and send these metrics to CloudWatch. First, I wrote this lambda function in Python, and then I had to re-write it in Java. As you may know, you need to use the cx_oracle module to connect Oracle Databases with Python. This extension module requires some libraries shipped by Oracle Database Client (oh God!). It’s a little bit tricky to pack it for the AWS Lambda.

Here’s the main class which a Lambda function can use:

Here is the step-by-step explanation of the above script:

You may notice a lot of “System.getenv” calls. I used it to read the environment parameters from the Lambda function.


You can download the Maven project from my GitHub repository. After you build the maven project, you need to upload the JAR file to your S3 bucket:

aws s3 cp target/samplelambda-0.1-jar-with-dependencies.jar s3://yourbucketname/

I used this JAR file to create a lambda function through the AWS Lambda console. My package name is “com.gokhanatil.samplelambda”, my class name is “Monitoring”, and the function name is “handleRequest”. This is why I entered “com.gokhanatil.samplelambda.Monitoring::handleRequest” as the handler. Please note that you need to give the required permissions to grant access to CloudWatch (e.g. CloudWatchFullAccess) and AWSLambdaVPCAccessExecutionRole. You also need to enter the Virtual Private Cloud (VPC) information (Subnets: pick two subnets that can reach your Oracle instance. Security groups: select one that gives you access to your Oracle instance).

To schedule this job to run periodically, you can use “CloudWatch events”. This event will be triggered every 15 minutes and launch the lambda function.


After enabling the lambda function, new metrics appear in the CloudWatch dashboard. It’s possible to create an alarm for these metrics using the console or AWS CLI commands.