在 Linux (Mageia) 上的 NetBeans 中从 Java 应用程序连接到 MariaDB

2022-01-15 00:00:00 mariadb mysql netbeans jdbc java

我正在尝试通过一个简单的 java 应用程序连接到 Mariadb 中的数据库，但连接被告知不成功并引发异常.我已经使用 mysql 完成了类似的连接，并且工作正常.问题可能出在这里的驱动程序上.

I am trying to connect to a database in Mariadb through a simple java application but the connection is told to be unsuccessful and an Exception is thrown. I have done the similar connection using mysql and it was working correctly. The problem is maybe with the driver here.

 try{
          Class.forName("org.mariadb.jdbc.Driver");  

        Connection connection = DriverManager.getConnection(  
                "jdbc:mariadb://localhost:3306/project", "root", "");  
        Statement statement = connection.createStatement(); 

        String uname="xyz",pass="abc";
       statement.executeUpdate("insert into user values('"+uname+"','"+pass+"')");}//end of try block

我在网上寻找帮助，发现 MariaDB Client Library for Java Applications 提供的驱动程序类不是 com.mysql.jdbc.Driver 而是 org.mariadb.jdbc.Driver！我相应地对其进行了更改，但似乎问题出在 try 块内的第一行.驱动程序根本没有加载.此外，我已将 mysql jar 文件添加到我的 java 应用程序的库中，如下面的屏幕截图所示.请帮我解决这个问题.

I looked up the internet for the help and came by that driver class provided by the MariaDB Client Library for Java Applications is not com.mysql.jdbc.Driver but org.mariadb.jdbc.Driver! I changed it accordingly but it seems the problem is with the very first line inside the try block. The driver is not loading at all. Also, I have added the mysql jar file to the libraries of my java application as in the screen-shot below. Please help me through this.

推荐答案

您似乎正在尝试使用 jdbc:mariadb://... 建立与 MariaDB 服务器实例的连接使用 MySQL JDBC 驱动程序.这可能行不通，因为 MySQL JDBC 驱动程序将使用 jdbc:mysql://...，无论它是连接到 MySQL 服务器还是 MariaDB 服务器.也就是说，连接字符串必须匹配正在使用的驱动程序(而不是正在访问的数据库服务器).

It appears that you are trying to use jdbc:mariadb://... to establish a connection to a MariaDB server instance using the MySQL JDBC Driver. That probably won't work because the MySQL JDBC Driver would use jdbc:mysql://..., regardless of whether it is connecting to a MySQL server or a MariaDB server. That is, the connection string must match the driver that is being used (rather than the database server being accessed).

MySQL 和 MariaDB 驱动程序应该可以互换，但在访问 MariaDB 服务器时使用 MariaDB 连接器似乎是明智的.对于它的价值，mariadb-java-client-1.1.7.jar

The MySQL and MariaDB drivers are supposed to be somewhat interchangeable, but it only seems prudent to use the MariaDB connector when accessing a MariaDB server. For what it's worth, the combination of mariadb-java-client-1.1.7.jar

和

Connection con = DriverManager.getConnection(
        "jdbc:mariadb://localhost/project", 
        "root", 
        "whatever");

为我工作.我从这里下载了适用于 Java 的 MariaDB 客户端库:

worked for me. I downloaded the MariaDB Client Library for Java from here:

https://downloads.mariadb.org/client-java/1.1.7/

我是通过

https://downloads.mariadb.org/

补充说明:

  1. Java 代码中不需要 Class.forName() 语句.

Mageia 下 MariaDB 的默认配置可能包括 /etc/my.cnf 中的 skip-networking 指令.如果您想通过 JDBC 连接到数据库，则需要删除(或注释掉)该指令，因为 JDBC 连接总是看起来像与 MySQL/MariaDB 的网络"连接，即使它们是来自 localhost.(您可能还需要将 bind-address 值调整为 0.0.0.0 之类的值.)

The default configuration for MariaDB under Mageia may include the skip-networking directive in /etc/my.cnf. You will need to remove (or comment out) that directive if you want to connect to the database via JDBC because JDBC connections always look like "network" connections to MySQL/MariaDB, even if they are connections from localhost. (You may need to tweak the bind-address value to something like 0.0.0.0 as well.)

相关文章