Oracle10g BLOB数据插入问题浅议

在Oracle中大数据类型一般常用oracle.sql.BLOB来表示，不同于mysql中的通用的java.sql.Blob接口，因此在插入图片数据到oracle的时候不能直接插入图片，一般采用oracle的empty_blob()函数，先生成空的BLOB对象插入到表中，然后再读取该记录，重新update图片数据到相应字段中；

举例如下：

创建表sql语句
drop sequence seq_changedata_infoid;
create sequence seq_changedata_infoid increment by 1 start with 1;
CREATE TABLE changedata_info (
  id number(20)  NOT NULL ,  
  version_id varchar2(20)   not null,
  sql_id number(20) default NULL,
  sql_content varchar2(256) default NULL,
  photo blob,
  PRIMARY KEY  (id)
 );

直接sql插入语句为：

insert into changedata_info(id,version_id,sql_id,sql_content,photo)values(1,'1200',1,'update ....',empty_blob())

程序代码如下：

public static void main(String[] args){
  
  
  BLOB blob = null; //图片类型
        OutputStream outputStream = null; //输出流
        File file = null; //文件
        InputStream inputStream = null; //输入流
       
        ResultSet rs = null;
  Statement sm = null;
  Statement smt = null;
  ResultSet rr = null;
 
 try {
  Class.forName("oracle.jdbc.driver.OracleDriver");
  Connection con = DriverManager
    .getConnection(
      "jdbc:oracle:thin:@localhost:1521:orcl",
      "system", "admin");
  
  con.setAutoCommit(false); //事物由程序员操作
  String sql = "";
  
  
  
//  DesEncrypt tm = new DesEncrypt();
//  tm.getKey("aabb");
//  String strDes = "";
//  String str ="";
  
  for(int i =8;i<11;i++){
   
   int id ;
   id = 1000 + i;
   String version_id = "20080813060839";
   
   int sql_id = i;
   
   String sql_content = "update ticketinfo set name = mingtian where id = 50006";
   
   String sqlInsert = "insert into changedata_info(id,version_id,sql_id,sql_content,photo)values("
   + id
   +","
   + version_id
   + ","
   + sql_id
   + ",'"
   + sql_content
   + "',"
   + "empty_blob()"
   + ")";
   
//   con.setAutoCommit(false); //事物由程序员操作
   smt = con.createStatement();
   
//   rs = sm.executeQuery(sqlInsert);//插入数据  ---当前图片为空
   smt.execute(sqlInsert);
   
   String sqlUpdate = "select photo from changedata_info where id='" + id + "'";
   
   sm = con.createStatement();
   ResultSet r= sm.executeQuery(sqlUpdate + " for update");
             if (r.next()) {
                   blob = (BLOB) r.getBlob(1);
                   byte [] photo = r.getBytes("photo");
                   outputStream = blob.getBinaryOutputStream();
                   file = new File("c://11//photo.jpg");//c://11//photo.jpg
                   inputStream = new FileInputStream(file);
                   byte[] b = new byte[blob.getBufferSize()];
                   int len = 0;
                   while ((len = inputStream.read(b)) != -1) {
                         System.out.println(len);
                         outputStream.write(b, 0, len);
                   }
             }
            
          
 
  }
    con.commit();
          con.close();
  
  
 
  
 } catch (ClassNotFoundException e) {
  // TODO Auto-generated catch block
  e.printStackTrace();
 } catch (SQLException e) {
  // TODO Auto-generated catch block
  e.printStackTrace();
 }catch(Exception e){
  e.printStackTrace();
 }
}

此代码经过测试，与mysql的图片插入做过比较之后有所感悟，所以唠叨一下....;-)