(Mysql) Data Writer problem 0:614:605:749


I am trying to use the Data Writer node, but a problem always pop up:

ERROR Database Reader      0:614:605:749 Execute failed: com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: Communications link failure

The last packet sent successfully to the server was 0 milliseconds ago. The driver has not received any packets from the server.


1) I am using a MAC OS.

2) I installed MAMP and created a Mysql server.

3) The config of the server is: 

Host localhost
Port 8889
User root
Password root
Socket /Applications/MAMP/tmp/mysql/mysql.sock

4) I followed the tutorial presented here: https://tech.knime.org/database-documentation and installed the "com.mysql.jdbc.Driver"

5) The screenshot of my Data Writer is attached.

If the file is broken, I did config like this:

Databse Driver: com.mysql.jdbc.Driver

Databse Url: jdbc:mysql://localhost:8889/Deputados



Table name: Teste

6) The screenshot of my workflow is attached.




Hello Eduardo,

the error message indicates a general problem to connect to the database. For more information have a look at this post on Stackoverflow. Can you connect to the database with another tool? KNIME also provides a dedicated MYSQL Connector node which comes with the necesary JDBC driver.



Hi Tobias, 

I found the problem! It was a configuration in the MAMP Pro. I did not see that it was not authorized to accept external connections! A simple check box... 

Thank you very much! 

Best Regards,