DB Query Reader: IllegalArgumentException: HOUR_OF_DAY: 2 -> 3

Hello to the Knime community,

I seem to have encountered an issue with this node: the “DB Query Reader”.

When I run this node to query a MySQL database (a table relatively important in size, of about ~ 70000 rows), it returns the following exception after a few seconds:

Exception reading data row: java.lang.IllegalArgumentException: HOUR_OF_DAY: 2 -> 3

I thought it could be something related to the table itself, so a problem originating from MySQL, but the “Database Reader (Legacy)” works perfectly well as a replacement. Even stranger is the fact if I open the configuration window for the “DB Query Reader”, and I click on “Evaluate”, the first 10 rows of the query are correctly being displayed.

This question does not seem to have been posted before. Any insight into what the problem might be, or the possible causes, would be deeply appreciated.

Thank you so very much!

Hello Berti1989,
please have a look at this MySQL driver bug. This error does happen for some timestamps that “do not exist” because of daylight saving time.
For more details on how to change the timezone in the MySQL Connector node have a look at this post.

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Hello Tobias,

Thank you so very much for your answer. I understand the problem a lot better. However, neither setting serverTimezone to UTC in MySQL Connector nor useLegacyDatetimeCode to true seem to solve the problem. I am still experiencing the same error with the DB Query Reader. Any thoughts?

Thank you again!

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