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  • java当中JDBC当中的transaction例子

    [学习笔记]

    7.jdbc的transaction例子:

    import java.sql.*;

    public class MySQlTransaction1 {

      public static void main(String[] args) throws SQLException {
    /*in my sql: create table Accounts(
                    ID int(4) not null,
                    NAME varchar(15),
                    BALANCE int(4),
                    primary key(ID)
                )  type=INNODB;
      insert into Accounts values(1,'wangwu',100);
      insert into Accounts values(3,'zhangsan',300);
      insert into Accounts values(4,'lisi',400);
         */
        Connection con = null;
        Statement s = null;
        try {
          Class.forName("com.mysql.jdbc.Driver");
          con = DriverManager.getConnection("jdbc:mysql://localhost:3306/test","root", "1234");
          //s = con.createStatement(ResultSet.TYPE_SCROLL_SENSITIVE,ResultSet.CONCUR_UPDATABLE);
    /*by default, whenever execute a sql, it will commit automatically,
    public void setAutoCommit(boolean autoCommit) throws SQLException
    Sets this connection's auto-commit mode to the given state. If a connection is in auto-commit 
    mode, then all its SQL statements will be executed and committed as individual transactions. 
    Otherwise, its SQL statements are grouped into transactions that are terminated by a call to
     either the method commit or the method rollback. By default, new connections are in
      auto-commit mode.        */

          s = con.createStatement();

          s.executeUpdate("update ACCOUNTS set BALANCE=508 where ID=3");
          System.out.println("333333");
    /*下一步中本来应为where ID=4, 但是却误写成了www ID=4, 所以有错,所以到catch中,但rollback时
     , 却做不成功, 因为是autocommited模式,所以上一句ID=3,就做真改成508了。*/      
          s.executeUpdate("update ACCOUNTS set BALANCE=608 www ID=4");
          System.out.println("444444");

          System.out.println("con = " + con);
         }
        catch (Exception e) {
          try{
            con.rollback();
            System.out.println("rollback successfully");
          }catch (Exception ex)
          {
            ex.printStackTrace();
          }
        }
        finally {
          s.close();
          con.close();
          System.out.println("successfully in finally");
        }
      }

    }

    文章转载自原文:https://blog.csdn.net/qq_43650923/article/details/100653000

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  • 原文地址:https://www.cnblogs.com/haima1949/p/11615675.html
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