• Java连接MySQL数据库


    1 下载安装Connector/J,下载地址:http://www.mysql.com/products/connector/。Connector/J是专门针对MySQL而开发的JDBC驱动程序包。
    2 将安装文件夹下的mysql-connector-java-5.1.36-bin.jar加入到环境变量的classpath。或者加入到项目的Java Build Path。
    3 JDBC基本编程的步骤:

    • 载入驱动
      其使用的方法有Class.forName()或者
      Class.forName().newInstance()或者
      new DriverName()
    • 连接数据库
      DriverManager.getConnection()
    • 运行SQL语句
      Connection.CreateStatement()
      Statement.executeQuery()
      Statement.executeUpdate()
    • 取得结果集
      while(rs.next())
    • 显示数据
      将数据库中的各种类型转化为java中的类型(getXXX)方法
    • 关闭
      close the resultset
      close the statement
      close the connection

    实例:

    package ms;
    import java.sql.Connection;
    import java.sql.DriverManager;
    import java.sql.SQLException;
    import java.sql.Statement;
    import java.sql.ResultSet;
    
    public class TestMySQL {
        public static void main(String[] args){
            ResultSet rs = null;
            Statement stmt = null;
            Connection conn = null;
            try{
                Class.forName("com.mysql.jdbc.Driver"); //创建该字符串标识的类的实例
                String url = "jdbc:mysql://localhost:3306/test"; //标识一个被注冊的驱动程序
                String user = "root";
                String pwd = "";
                conn = DriverManager.getConnection(url, user, pwd);
                stmt = conn.createStatement();
                String query = "select * from person where age > 18";
                rs = stmt.executeQuery(query);
                while (rs.next()){
                    String id = rs.getString("id");
                    String name = rs.getString(2);
                    int age = rs.getInt("age");
                    System.out.println(id + "	" + name + "	" + age);
                }
            }
            catch (ClassNotFoundException e){
                e.printStackTrace();
            }
            catch (SQLException e){
                e.printStackTrace();
            }
            finally {
                try{
                    if (rs != null){
                        rs.close();
                    }
                    if (stmt != null){
                        stmt.close();
                    }
                    if (conn != null){
                        conn.close();
                    }
                }
                catch (SQLException e){
                    e.printStackTrace();
                }
            }
        }
    }

    PreparedStatement的预处理语句:

    String sql = "insert into person values(?,?

    ,?)"; PreparedStatement pstmt = conn.prepareStatement(sql); pstmt.setString(1, "005"); pstmt.setString(2, "Zhao"); pstmt.setInt(3, 18); pstmt.executeUpdate();

    statement语句的批处理:

    Statement stmt = conn.createStatement();
    stmt.addBatch("insert into person values('006', 'Zeng', 26)");
    stmt.addBatch("insert into person values('007', 'Liu', 24)");
    stmt.addBatch("insert into person values('008', 'Zeng', 17)");
    stmt.executeBatch();

    PreparedStatement语句的批处理

    String sql = "insert into person values(?,?,?)";
    PreparedStatement pstmt = conn.prepareStatement(sql);
    pstmt.setString(1, "006");
    pstmt.setString(2, "Zeng");
    pstmt.setInt(3, 26);
    
    pstmt.setString(1, "007");
    pstmt.setString(2, "Liu");
    pstmt.setInt(3, 24);
    
    pstmt.setString(1, "008");
    pstmt.setString(2, "Zeng");
    pstmt.setInt(3, 17);
    pstmt.executeUpdate();
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  • 原文地址:https://www.cnblogs.com/bhlsheji/p/5243333.html
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