Getting Started with Talend Open Studio: Run and Debug Your Jobs
In the past blogs, we have learned how to install Talend Open Studio, how to build a basic job loading data into Snowflake, and how to use a tMap component to build more complex jobs. In this blog, we will enable you with some helpful debugging techniques and provide additional resources that you can leverage as you continue to learn more about Talend Open Studio.
As with our past blogs, you are welcome to follow along in our on-demand webinar. This blog corresponds with the last video of the webinar.
In this tutorial, we will quickly address how to successfully debug your Talend Jobs, should you run into errors. Talend classifies errors into two main categories: Compile errors and Runtime errors. A Compile error prevents your Java code from compiling properly (this usually includes syntax errors or Java class errors). A Runtime error prevents your job from completing successfully, resulting in the job failing during execution.
In the previous blog, we designed a Talend job to generate a Sales report to get data into a Snowflake cloud data warehouse environment. For the purposes of this blog, we have altered that job, so when we try to run it, we will see both types of errors. In this way, we can illustrate how to resolve both types of errors.
Resolving Compile Errors in Talend Open Studio
Let’s look at a compile error. When we execute this job in Talend Studio, it will first attempt to compile, however, the compile will fail with the below error.
You can review java error details within the log, which states that the "quantity cannot be resolved or is not a field". Conveniently, it also highlights the component the error is most closely associated to.
To locate the specific source of the problem within the tMap component, you can either dive into the tMap and search yourself OR you can switch to the Code view. Although you cannot directly edit the code here, you can select the red box highlighted on the right of the scroll bar to bring you straight to the source of the issue.
In this case, the arithmetic operator is missing from the Unit Price and Quantity equation.
Next, head into the tMap component and make the correction to the Unit Price and Quantity equation by adding a multiplication operator (*) between Transactions.Unit_Price and Transactions.qty. Click Ok and now run the job again.
And now you see the compile error has been resolved.
Resolving Runtime Errors in Talend Open Studio
Next, the job attempts to send the data out to Snowflake. And a runtime error occurs. You can read the log and it says, "JDBC driver not able to connect to Snowflake" and "Incorrect username or password was specified".
To address this issue, we’ll head to the Snowflake component and review the credentials. It looks like the Snowflake password was incorrect, so re-enter the Snowflake password, and click run again to see if that resolved the issue.
And it did! This job has been successfully debugged and the customer data has been published to the Snowflake database.
This was the last of our planned blogs on getting started with Talend Open Studio, but there are other resources that you can access to improve your skills with Talend Open Studio. Here are some videos that we recommend you look at to strengthen and add on to the skills that you have gained from these past four blogs:
Joining Two Data Sources with the tMap Component – This tutorial will give you some extra practice using tMap to join your data complete with downloadable dummy data and PDF instructions.
Adding Condition-Based Filters Using the tMap Component – tMap is an incredibly powerful and versatile component with many uses, and in this tutorial, you will learn how to use tMap and its expression builder to filter data based on certain criteria.
Using Context Variables – Learn how to use context variables, which allow you to run the same job in different environments.
For immediate questions, be sure to visit our Community, and feel free to let us know what types of tutorials would be helpful for you.