利用数据库如何存入BLOB格式图片,并从数据库中取出BLBO格式图片
这两天需要在图片存储性能方面做一些实验,无非就是两种方法,一是将图片以BLOB式存入数据库中,二是将图片路径存入数据库中,然后从数据库中提取出来。 实验数据是从1000张图片中遍历取出100张,样本比较小哈。。。。 下面贴出代码 数据库我使用的是国产达
这两天需要在图片存储性能方面做一些实验,无非就是两种方法,一是将图片以BLOB格式存入数据库中,二是将图片路径存入数据库中,然后从数据库中提取出来。
实验数据是从1000张图片中遍历取出100张,样本比较小哈。。。。
下面贴出代码
数据库我使用的是国产达梦数据库,如果要改其他的话也比较简单。
//package lianjie; import java.io.File; import java.io.FileInputStream; import java.io.FileNotFoundException; import java.io.FileOutputStream; import java.io.IOException; import java.io.InputStream; import java.io.OutputStream; import java.sql.Blob; 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 javax.imageio.ImageIO; public class DmTest { // 定义 DM JDBC 驱动串 String jdbcString = "dm.jdbc.driver.DmDriver"; // 定义 DM URL 连接串 String urlString = "jdbc:dm://localhost:5236/"; // 定义连接用户名 String userName = "SYSDBA"; // 定义连接用户口令 String password = "SYSDBA"; static //定义sql语句 //String sqlString ="create table yujin3(a int,b int,c int);"; String sqlString1="insert into yujin3 values(123,14,1234);"; // 定义连接对象 static Connection conn = null; static Statement stmt = null; static PreparedStatement ps = null; static ResultSet rs = null; //private static String sqlString1; /* 加载 JDBC 驱动程序 * @throws SQLException 异常 */ public void loadJdbcDriver() throws SQLException { try { System.out.println("Loading JDBC Driver..."); // 加载 JDBC 驱动程序 //DriverManager.registerDriver(new dm.jdbc.driver.DmDriver()); Class.forName(jdbcString); } catch (ClassNotFoundException e) { throw new SQLException("Load JDBC Driver Error1: " + e.getMessage()); } catch (Exception ex) { throw new SQLException("Load JDBC Driver Error : " + ex.getMessage()); } } public void connect() throws SQLException { try { System.out.println("Connecting to DM Server..."); // 连接 DM 数据库 conn = DriverManager.getConnection(urlString, userName, password); } catch (SQLException e) { throw new SQLException("Connect to DM Server Error : " + e.getMessage()); } } /* 关闭连接 * @throws SQLException 异常 */ public void disConnect() throws SQLException { try { // 关闭连接 conn.close(); System.out.println("close"); } catch (SQLException e) { throw new SQLException("close connection error : " + e.getMessage()); } } public static void main(String args[]) { DmTest basicApp = new DmTest(); // 加载驱动程序 try { basicApp.loadJdbcDriver(); } catch (SQLException e2) { // TODO Auto-generated catch block e2.printStackTrace(); } try { basicApp.connect(); } catch (SQLException e2) { // TODO Auto-generated catch block e2.printStackTrace(); } String sql = "DROP TABLE blobtest"; //String sql=null; try { stmt = conn.createStatement(); System.out.println(sql); stmt.executeUpdate(sql); //创建表 sql = "CREATE TABLE blobtest(" + "b_title int,"+ "b_text Blob"+ ")"; System.out.println(sql); stmt.executeUpdate(sql); System.out.println("创建数据表成功!"); sql="INSERT INTO blobtest(b_title,b_text)VALUES(?,?)"; ps = conn.prepareStatement(sql); //插入图片 //File file = new File("F:\\image\\yahoo.jpg"); for(int i=0;i <p><span>然后在相应路径下面就生成了100张图片,速度还是比较快的,关于实验数据大家可以去网上下载,或者减少样本,一两张都可以,只是要稍微修改下代码就行。</span><br> </p>

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