No Database Specified: Resolving "No Database Selected" Error in MySQL Retrieval
When attempting to retrieve data from a MySQL database using JDBC, a common error encountered is "java.sql.SQLException: No database selected." This error occurs when the database name is not specified in the connection URL used to establish a connection to the database.
To address this issue, the connection URL must include the name of the database to be accessed. The correct format for a MySQL connection URL is:
jdbc:mysql://hostname:port/database_name
For example, if your database is hosted on a server with the hostname "localhost" and port "3306", and the database name is "mydb," the correct connection URL would be:
String url = "jdbc:mysql://localhost:3306/mydb";
By specifying the database name in the connection URL, you ensure that the connection is established to the correct database and that data can be retrieved successfully.
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