Talend Migration from 4.X to 5.X

Recently, we started working on Talend Migration from 4.X to 5.X. One biggest surprise we encountered was, the Talend migration of jobs happens automatically without a message for confirmation.

Something in lines of "The migration is about to start. Do you want to proceed, Yes/No"

This means that if you opened a Talend 4.X job in TIS/TOS 5.X studio, the job is automatically migrated to 5.X. Since, we had an unplanned/accidental migration, we had to revert the code back to 4.X in sub-version. But we had several issues when reverting the code back. This post is to share our experiences about the migration.

Cannot find Talend.Project error. Classic error!! If you look in your subversion, you would see the talend.project file but the studio complains that it cannot find it. We still do not know which one action solved this error but doing the following helped us resolve the error.

1. Release all the locks in Talend using TAC.
2. Make sure that the project url to subversion is reachable.
3. Make sure that the account used to add a project in subversion has sub-version access privileges to the project.
4. Make sure that the project references has the authorization set up properly.
5. Make sure that the subversion url is valid and the credentials are good.
6. Make sure each user in the TAC has an svn login configured.

Cannot give a detailed screenshots for this exercise but let me know if you run into a similar issue during migration. Would be happy to help!

Error - Talend.Project doesn't exist

Happy Talending!

Praveena

Commenting GOTCHA that a Talend Novice should keep in mind

COMMENTING in QUERY components of Talend can be a pain as the error messages that you get due to commenting in SQL style will not be intuitive.

JAVA commenting style -
// For single line commenting
/* .... */ Multi line commenting

SQL commenting style-
-- For single line commenting.
/* .... */ Multi line commenting

The QUERY in a query component like MySqlInput is JAVA string behind the scenes. So commenting using the hiphens(--) in SQL style will result in an error. So it is wise to choose /* */ multi line JAVA/SQL style comments  to be safe than sorry.

Happy Talending!
-Praveena

java.lang.RuntimeException: For update, Schema must have a key

This is a famous Talend runtime Exception that a novice could run into several times especially when using an DBoutput component and updating the rows. Talend Forums are not quite helpful in resolving this issue. The fix is very straightforward but very unintuitive to know about it in the first attempt.

The fix involves checking the "Update-Key" found in the Advanced Settings of the Component view.

Above is the screenshot of how to fix the Exception. Go to the "Component" tab --> "Advanced Settings" --> Update Key

Check the appropriate column in the check boxes under the update key heading. You might have to scroll down the page to find this setting.