java.sql.SQLException: Access denied for user

The full error message may be : java.sql.SQLException: Access denied for user 'root'@'localhost' (using password : YES) or java.sql.SQLException: Access denied for user 'root'@'localhost' (using password: NO) When we try to connect to a database through JDBC with wrong username or password - we see this error message. See the sample code below: Connection connection = DriverManager.getConnection("jdbc:mysql://localhost:3306/DatabaseName","root","mypassword"); In...

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com.mysql.jdbc.exceptions.jdbc4.MySQLSyntaxErrorException: Unknown database

Trying to connect to a MySQL server from Java? But seeing the error "Unknown database"? The reason is that the database does not exist in the MySQL server. You might have accidentally misspelled the database name in the JDBC connection url. See the code below: Connection connection = DriverManager.getConnection("jdbc:mysql://localhost:3306/sales","username","password"); Here sales is the database...

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com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: Communications link failure

This error message may include the following text also: "The last packet sent successfully to the server was 0 milliseconds ago. The driver has not received any packets from the server." When we try to connect to a MySQL server "Communications link failure" error may occur for any of the following errors: i) MySQL server is not running. Check for this and run the sever if it is stopped. ii)...

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ClassNotFoundException: com.mysql.jdbc.Driver

This error occurs when the required JDBC driver file is not in the CLASSPATH. Also, if the driver name is not correct ClassNotFoundException occurs. To solve this problem, at first check the driver name; if the driver name is correct, do one of the followings as per requirement. i) Add an entry for the driver file (mysql-connector-java-5.1.10.jar, for example) in the CLASSPATH variable. or ii)...

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