java通过Access_JDBC30读取access数据库时无法获取最新插入的记录以及使用ucanaccess连接Access数据库
前言:一般使用的编译环境是java SE 1.8,不支持odbc的连接方式,所以可以用jdbc的连接方式。
jdbc存在数据获取刷新问题,建议使用odbc连接。odbc连接注意环境版本号!
1、编写了一个循环程序,每几秒钟读取一次,数据库中最新一行数据
连接access数据库的方法和查询的信息。之后开一个定时去掉用。
package javacommon.util; import java.sql.Connection; import java.sql.DriverManager; import java.sql.PreparedStatement; import java.sql.ResultSet; import java.sql.SQLException; import java.sql.Statement; import com.ybb.DBConnection; /** * * @author ybb * 连接Access数据库 * java通过Access_JDBC30获取access数据库数据,取不到最新的数据 */ public class AccessDBUtil { private static final String DRIVER="com.hxtt.sql.access.AccessDriver"; private static final String URL="jdbc:Access:///G:/ceshi/ceshi.mdb"; private static final String USER=""; private static final String PASSWORD=""; public static Connection getConnection(){ try { Class.forName(DRIVER); } catch (ClassNotFoundException e) { e.printStackTrace(); } try { Connection connection = DriverManager.getConnection(URL, USER, PASSWORD); return connection; } catch (SQLException e) { return null; } } public static void colseConnection(Connection conn){ try { if(conn!=null&&!conn.isClosed()){ conn.close(); } } catch (Exception e) { e.printStackTrace(); } } public static void myclose(Connection con,PreparedStatement ps){ try { if (con!=null&&!con.isClosed()) { con.close(); } if (ps!=null) { ps.close(); } } catch (Exception e) { e.printStackTrace(); } } public static void myclose(Connection con,PreparedStatement ps,ResultSet rs){ try { if (con!=null&&!con.isClosed()) { con.close(); } if (ps!=null) { ps.close(); } if (rs!=null) { rs.close(); } } catch (Exception e) { e.printStackTrace(); } } /** * 测试 * */ public static void main(String[] args){ Connection connnect = null; while(true){ try{ connnect = AccessDBUtil.getConnection(); if(connnect!=null){ System.out.println(connnect+"\n连接成功"); }else{ System.out.println("连接失败"); } Statement stat = connnect.createStatement(); ResultSet rs = stat.executeQuery("select * from CYJ_PD_QTJL"); if(rs!=null){ while(rs.next()){ System.out.println(rs.getString(1)+"\t"+rs.getString(2)); } } Thread.sleep(5000); }catch(Exception e){ e.printStackTrace(); }finally{ colseConnection(connnect);//关闭链接 } } } }
2、当手动向对应的access数据库中CYJ_PD_QTJL表
添加数据时,查询不到刚添加的数据。需要重启此程序才能查询到。
3、为了解决此问题更换驱动。用ODBC连接完美解决。
package com.ybb; import java.sql.Connection; import java.sql.DriverManager; import java.sql.PreparedStatement; import java.sql.ResultSet; import java.util.Properties; /** * * @author ybb * 连接access数据 * 获取access数据库数据,可以取到最新的数据 * 2019年4月16日 下午2:48:33 */ public class DBConnection { /** * 该方法用来连接数据库 * @param db:数据源名称 * */ public static Connection getDBConnection(){ try{ Class.forName("sun.jdbc.odbc.JdbcOdbcDriver");//注册驱动 //Access中的数据库默认编码为GBK,本地项目为UTF-8,若不转码会出现乱码 Properties p = new Properties(); p.put("charSet", "GBK"); Connection connect= DriverManager.getConnection("jdbc:odbc:ceshi",p); return connect; }catch(Exception e){ e.printStackTrace(); return null; } } /** * 该方法用来执行SQL并返回结果集 * */ public static ResultSet selectQuery(String sql){ try{ PreparedStatement stmt = getDBConnection().prepareStatement(sql); ResultSet rs = stmt.executeQuery();//执行SQL return rs; }catch(Exception e){ e.printStackTrace(); return null; } } /** * 测试 * */ public static void main(String[] args){ while(true){ try{ Connection connnect = DBConnection.getDBConnection(); if(connnect!=null){ System.out.println(connnect+"\n连接成功"); }else{ System.out.println("连接失败"); } ResultSet rs1 = selectQuery("select * from CYJ_PD_QTJL"); if(rs1!=null){ while(rs1.next()){ System.out.println(rs1.getString(1)+"\t"+rs1.getString(2)); } } Thread.sleep(5000); }catch(Exception e){ e.printStackTrace(); }finally{ // closeConn();//关闭链接 } } } }
4、此时手动向CYJ_PD_QTJL表中添加数据。可以立刻查询到刚添加的数据。
5、方式二:使用ucanaccess连接Access数据库。
package com.test; import java.sql.Connection; import java.sql.DriverManager; import java.sql.PreparedStatement; import java.sql.ResultSet; import java.sql.Statement; /** * * @author Administrator * */ public class Access { /** * Access数据库Connection */ private Connection connection; static { try { Class.forName("net.ucanaccess.jdbc.UcanaccessDriver");//加载ucanaccess驱动 } catch (Exception e) { throw new RuntimeException(e.getMessage()); } } public Connection getAccessConnection(String path, String user, String pwd) { try { //获取Access数据库连接(Connection) this.connection = DriverManager.getConnection("jdbc:ucanaccess://" + path, user, pwd); } catch (Exception e) { throw new RuntimeException(e.getMessage()); } return this.connection; } public static void main(String[] args) throws Exception { Access access=new Access(); Connection connection = access.getAccessConnection("F:\\Access\\test.accdb", "", ""); // access.insert(connection); access.select(connection); } /** * Access插入(使用了预编译) */ public int insert(Connection connection) throws Exception { // ? 是 JDBC 预编译的占位符 PreparedStatement statement=connection.prepareStatement("insert into student(name,address,age) values(?,?,?)"); statement.setString(1, "Ybb"); statement.setString(2, "湖南省、长沙市、岳麓区"); statement.setInt(3, 20); int result = statement.executeUpdate(); statement.close(); connection.close(); System.err.println("添加数据成功"); return result; } /** * Access删除 */ public int delete(Connection connection) throws Exception { Statement statement = connection.createStatement(); int result = statement.executeUpdate("delete from student where id=3"); statement.close(); connection.close(); return result; } /** * * @param connection * @return * @throws Exception */ public int update(Connection connection) throws Exception { Statement statement = connection.createStatement(); int result = statement.executeUpdate("update student set address='湖南省、长沙市、雨花区' where id=1"); statement.close(); connection.close(); return result; } /** * Access查询 * * @param connection 连接 * @throws Exception 异常 * @date: 2022 */ public void select(Connection connection) throws Exception { Statement statement = connection.createStatement(); ResultSet result = statement.executeQuery("select * from student"); while (result.next()) { System.out.print(result.getString("id") + "\t"); System.out.print(result.getString("name") + "\t"); System.out.print(result.getString("address") + "\t"); System.out.print(result.getString("age") + "\t"); System.out.println(); } statement.close(); connection.close(); } }
6、ucanaccess连接Access数据库,源码下载链接
链接:https://pan.baidu.com/s/1iKTsFYxg4TNA1BRmctHWyw
提取码:w53g