Oracle 下操作blob字段是否会产生大量redo

操作blob字段是否会产生大量redo,答案是不会,下面来做一个实验,测试Oracle数据库版本是11.2.0.1.0:

CentOS 6.4下安装Oracle 11gR2(x64)

Oracle 11gR2 在VMWare虚拟机中安装步骤

Debian 下 安装 Oracle 11g XE R2
 
--创建一张表做测试之用
 
create table test_blob
 (
  id number,
  tupian blob
 );

import java.io.FileInputStream;
import java.io.OutputStream;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;

import oracle.sql.BLOB;

public class BlobExample {
    static final String driver_class  = "oracle.jdbc.driver.OracleDriver";
    static final String connectionURL = "jdbc:oracle:thin:@10.10.15.25:1521:orcl";
    static final String userID        = "test";
    static final String userPassword  = "test";

private void insertTestBlob() {
        Connection conn=null;
        Statement stm=null;
        ResultSet rs=null;
        BLOB blob = null;
        FileInputStream fin=null;
        OutputStream out=null;
        try{
            conn = DriverManager.getConnection(connectionURL, userID, userPassword);
            stm = conn.createStatement();
            conn.setAutoCommit(false);
            String sql = "insert into test_blob values(1,EMPTY_BLOB())";
            stm.executeUpdate(sql);
            rs = stm.executeQuery("SELECT tupian FROM test_blob WHERE id=1 FOR UPDATE ");
          fin = new FileInputStream("d://20130317.jpg");
          byte[] blobBuf = new byte[(int)fin.available()];
          fin.read(blobBuf);
          fin.close();

if(rs.next()) {
            blob = (oracle.sql.BLOB)rs.getBlob(1);
            out = blob.getBinaryOutputStream();
            out.write(blobBuf);
            out.close();
            conn.commit();
          }
        }catch(Exception e){
            e.printStackTrace();
        }finally{
            try {
                rs.close();
                stm.close();
                conn.close();
            } catch (SQLException e) {
                e.printStackTrace();
            }
        }
    }
    public static void main(String args[]){
        BlobExample  blobClobExample = new BlobExample();
        blobClobExample.insertTestBlob();
    }
}

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