java连接oracle或者mysql

ゝ一纸荒年。 2022-05-19 13:06 172阅读 0赞

由于经常忘记怎么连接oracle或者mysql ，所以记录一下

/* 先引入jar包：orcle包类似ojdbc14.jar
    				mysql包类似mysql-connector-java-5.1.10
    			本地装orcle的话，可以在安装目录的 E:\oracle\product\10.2.0\db_1\jdbc\lib
    			 如果没有的话，以上的包都可以在maven中央仓库或者对应的官网上找得到
    mysql: 
        
    	 driver :com.mysql.jdbc.Driver;
    	 url : jdbc:mysql://localhost:3306/bojoydb
    	 
    orcle :  driver :oracle.jdbc.OracleDriver
             url: jdbc:oracle:thin:@192.168.x.xxx:1521:dbname
       连接步骤：
         1.注册驱动
    	 2.DriverManager获取connection对象
    	 3.connection对象查询得到ResultSet
    	 4，遍历结果集ResultSet
    	 5.关闭连接
         以下是最简单的连接方式，一般的话，数据库的配置放在properties里面，对应的获取Connection 也都
         是封装成相应的工具类，然后通过类去调用	 
    */
    package test;
    
    import java.sql.CallableStatement;
    import java.sql.Connection;
    import java.sql.DriverManager;
    import java.sql.ResultSet;
    import java.sql.SQLException;
    import java.sql.Statement;
    
    public class TestOracle {
    	public static void main(String[] args) throws SQLException {
    		 String userName = "root";
    	     String password = "123456";
    	     String driver = "oracle.jdbc.OracleDriver";
    	     String url = "jdbc:oracle:thin:@192.168.1.123:1521:testdb";
    	     Connection connection =null;
    	     Statement createStatement= null;
    	     ResultSet executeQuery =null;
    		try{
    			
    			Class.forName(driver);
    			
    			connection = DriverManager.getConnection(url,userName,password);
    			
    			String str = "select count(*) as te  from t_user ";
    			
    			createStatement = connection.createStatement();
    			
    			
    			 executeQuery = createStatement.executeQuery(str);
    			while(executeQuery.next()){
    				String string = executeQuery.getString("te");
    				System.out.println("总数："+string);
    			}
    		}catch(Exception e){
    			e.printStackTrace();
    		}finally {
    			
    			if (executeQuery!=null) executeQuery.close();
    			if (createStatement!=null) createStatement.close();
    			if (connection!=null) connection.close();
    		}
    		
    	}
    
    }