zoukankan      html  css  js  c++  java
  • QueryRunner实现查询操作

    public static  void insert() throws SQLException{
            QueryRunner qr =new QueryRunner();
            String sql ="insert into sort values(?,?,?)";        
            Object[] obj ={9,"橡皮擦","好吃又大补"};
            Connection conn =JDBCUtils.getConnection();
            int row= qr.update(conn,sql,obj);
            conn.close();
            System.out.println(row);
        }
        public static void update() throws SQLException{
            QueryRunner qr =new QueryRunner();
            String sql ="update sort set sname=? , sdesc =? where sid =?";
            Object[] obj ={"排骨","好吃",9,};
            Connection conn =JDBCUtils.getConnection();
            int row= qr.update(conn,sql,obj);
            conn.close();
            System.out.println(row);
        }
        public static void delect() throws SQLException{
            QueryRunner qr =new QueryRunner();
            String sql ="delete from sort  where sid =?";        
            Connection conn =JDBCUtils.getConnection();
            int row= qr.update(conn,sql,9);
            conn.close();
            System.out.println(row);
        }
        public static void find1() throws SQLException{
            QueryRunner qr =new QueryRunner();
            String sql ="select * from sort";        
            Connection conn =JDBCUtils.getConnection();
            //获取第一条记录
            Object[] obj =qr.query(conn, sql,new ArrayHandler());
            for(Object o:obj){
                System.out.print(o+"...");
            }
        }
        public static void find2() throws SQLException{
            QueryRunner qr =new QueryRunner();
            String sql ="select * from sort";        
            Connection conn =JDBCUtils.getConnection();
            //获取全部记录
            List<Object[]> list =qr.query(conn, sql,new ArrayListHandler());
            for(Object[] obj:list){
                for(Object o1:obj){
                    System.out.print(o1+"...");
                }
                System.out.println();
            }
        }
        public static void find3() throws SQLException{
            QueryRunner qr =new QueryRunner();
            String sql ="select * from sort";        
            Connection conn =JDBCUtils.getConnection();
            //获取第一条记录(封装成对象)
            sort s =qr.query(conn,sql,new BeanHandler<sort>(sort.class));
            System.out.println(s);
        }
        public static void find4() throws SQLException{
            QueryRunner qr =new QueryRunner();
            String sql ="select * from sort";        
            Connection conn =JDBCUtils.getConnection();
            //获取所有记录(封装成对象)
            List<sort> list =qr.query(conn,sql,new BeanListHandler<sort>(sort.class));
            for(sort s:list){
                System.out.println(s);
            }
        }
        public static void find5() throws SQLException{
            QueryRunner qr =new QueryRunner();
            String sql ="select * from sort";        
            Connection conn =JDBCUtils.getConnection();
            //获取sname列所有数据
            List<String> list =qr.query(conn,sql,new ColumnListHandler<String>("sname"));
            for(String s:list){
                System.out.println(s);
            }
            conn.close();
        }
        public static void find6() throws SQLException{
            QueryRunner qr =new QueryRunner();
            String sql ="select count(*) from sort";        
            Connection conn =JDBCUtils.getConnection();
            //用于单数据。例如select count(*) from 表操作。
            Long count =qr.query(conn,sql,new ScalarHandler<Long>());                    
            System.out.println(count);
            conn.close();
        }
        public static void find7() throws SQLException{
            QueryRunner qr =new QueryRunner();
            String sql ="select * from sort";        
            Connection conn =JDBCUtils.getConnection();
            //将结果集第一行封装到Map集合中,Key 列名, Value 该列数据
            Map<String ,Object> map =qr.query(conn,sql,new MapHandler());                    
            for(String key:map.keySet()){
                System.out.print(key+"..."+map.get(key));
            }
            conn.close();
        }
        public static void find8() throws SQLException{
            QueryRunner qr =new QueryRunner();
            String sql ="select * from sort";        
            Connection conn =JDBCUtils.getConnection();
            //将结果集第一行封装到Map集合中,Key 列名, Value 该列数据,Map集合存储到List集合
            List<Map<String ,Object>> list =qr.query(conn,sql,new MapListHandler());                    
            for(Map<String ,Object> m:list){
                for(String s:m.keySet()){
                    System.out.print(s+"..."+m.get(s));
                }
                System.out.println();
            }
            conn.close();
        }
  • 相关阅读:
    linux cd命令的重要用法:cd -,cd ~
    linux ls命令的重要用法:按照文件大小排序和按照时间排序
    Linux中默认的shell如何切换为其他类型的shell
    centos 7网卡配置文件详解(ifcfg-ens33)
    linux分区规划
    final关键字
    分布式事务
    读写分离-读仍走主库的问题
    Dockerfile指令
    Docker命令总结【第一本docker书】
  • 原文地址:https://www.cnblogs.com/Jxliu/p/9300069.html
Copyright © 2011-2022 走看看