MySQL Could not create connection to database serve error

Question

I am trying to connect to MySQL server with Java. I am getting the following error:

Exception in component tDBInput_1 (job_Database)

com.mysql.jdbc.exceptions.jdbc4.MySQLNonTransientConnectionException: Could not create connection to database server.

at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)

at sun.reflect.NativeConstructorAccessorImpl.newInstance(Unknown Source)

at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(Unknown Source)

at java.lang.reflect.Constructor.newInstance(Unknown Source)

at com.mysql.jdbc.Util.handleNewInstance(Util.java:409)

at com.mysql.jdbc.Util.getInstance(Util.java:384)

at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:1013)

at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:987)

at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:973)

at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:918)

at com.mysql.jdbc.ConnectionImpl.connectOneTryOnly(ConnectionImpl.java:2588)

at com.mysql.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:2321)

at com.mysql.jdbc.ConnectionImpl.<init>(ConnectionImpl.java:832)

at com.mysql.jdbc.JDBC4Connection.<init>(JDBC4Connection.java:46)

at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)

I used the same Java code in a different machine, it worked. So I think there is no problem with the code.

Answer 1

This error occurs when you are trying to connect to MySQL database but the MySQL service is not running/available. If you have not installed, first install MySQL server using this command:

$ sudo apt-get update
$ sudo apt-get install mysql-server

And then to start MySQL service, run any one of the following commands:

$ sudo service mysql start

or

$ sudo /etc/init.d/mysql start

And then run your code, it should work

Comments

Where should we execute this command?

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Hi,

You need to execute in your server command line. Open the terminal and run the command.

Answer 2

When I am trying to connect netbeans with MySQL then it's showing this error:

cannot establish a connection to jdbc MySQL. Could not create connection to database server. 

How to fix it.

Comments

Is your MySQL database working fine? Check by executing the following command

mysqladmin -u root -p ping 

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어디에 집어 넣어야하나요?

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안녕하세요.

위의 쿼리를 실행하기 위해 MySQL 서버를 설치해야합니다

Answer 3

Pls check that you have MySQL server running(if your running mysql command line client).

IF you are running Mysql command line client then delete it and download from: https://dev.mysql.com/downloads/windows/installer/8.0.html

Also watch this video and follow the steps: https://www.youtube.com/watch?v=u96rVINbAUI

I think mysql workbench and mysql server is needed mandatory!!!

It worked from me!!!