topic Re: German Umlauts wrong via JDBC in Data Engineering

German Umlauts wrong via JDBC

jordan72 — Mon, 30 Jun 2025 11:17:04 GMT

Hi,

I have the issue that German Umlauts are not getting retrieved correctly via the JDBC driver.

It shows M�nchen instead of München.

I load the driver in my java app via:

<groupId>com.databricks</groupId>
<artifactId>databricks-jdbc</artifactId>
<version>2.7.3</version>

and set the charsets via:

System.setProperty("file.encoding", "UTF-8");
System.setProperty("sun.jnu.encoding", "UTF-8");

In the Databricks UI everything look correctly. The column type is STRING.

Regards

Volker Jordan

Re: German Umlauts wrong via JDBC

szymon_dybczak — Mon, 30 Jun 2025 12:03:05 GMT

Hi @jordan72 ,

Maybe try to add to your jdbc connection url following parameters:

- CharacterEncoding=UTF-8;

- UseUnicode=true;

- CharSet=UTF-8;

String url = "jdbc:databricks://<your-host>:443/default;transportMode=http;ssl=1;httpPath=<http-path>;AuthMech=3;UID=token;PWD=<token>;CharSet=UTF-8;characterEncoding=UTF-8;UseUnicode=true;";

Re: German Umlauts wrong via JDBC

jordan72 — Mon, 30 Jun 2025 12:19:37 GMT

I already tried all those parameters, but nothing changed.

Surprisingly, in DataGrip (which also used the JDBC driver) the results are correct. And I copied the url from DataGrip into a raw Java IDE, and here it does not work.

Re: German Umlauts wrong via JDBC

szymon_dybczak — Mon, 30 Jun 2025 12:59:27 GMT

Ok, thanks for additional information. So maybe the issue is somehow related to JVM environment.
I noticed that you're setting following property: System.setProperty("file.encoding", "UTF-8");
Java sets file.encoding once at JVM startup — setting it with System.setProperty at runtime has no effect on string decoding in most libraries, including JDBC drivers.

Try to launch your application with following VM option.

java -Dfile.encoding=UTF-8

Re: German Umlauts wrong via JDBC

szymon_dybczak — Mon, 30 Jun 2025 13:03:58 GMT

Another thought, you can check if this is not problem with your IDE configuration. Assuming you're using Intellij, then check your file encodings settings: Settings -> Editior -> File encodings.

Use the UTF-8, Luke! File Encodings in IntelliJ IDEA | The IntelliJ IDEA Blog

Re: German Umlauts wrong via JDBC

jordan72 — Mon, 30 Jun 2025 13:52:07 GMT

hm, now its getting even more weird. I usually use NetbeansIDE. I now tried the same code with Eclipse and here it worked without any special options. In Netbeans, even with

-Dfile.encoding=UTF-8

there is no change. Does anyone know what can lead Netbeans to this behaviour ?

Re: German Umlauts wrong via JDBC

szymon_dybczak — Mon, 30 Jun 2025 14:13:10 GMT

Ok, so that only confirms that this problem is not related to driver. Rather, this is weird quirk of Netbeans.
In netbeans it's not sufficient to use only option -Dfile.encoding=UTF-8.
Please follow approach suggested in following stackoverflow thread, depending on Java version you're using

java - How to use UTF-8 character in Netbeans - Stack Overflow

Re: German Umlauts wrong via JDBC

jordan72 — Mon, 30 Jun 2025 15:40:48 GMT

ok, so it seems that it has something to do with the newly introduced native.encoding system property.

So In Netbeans you have to provide -Dstdout.encoding=utf-8 to the vm if you are using JDK21.

Re: German Umlauts wrong via JDBC

szymon_dybczak — Mon, 30 Jun 2025 15:44:19 GMT

Yes, this is exactly what the link I provided above suggested: