blob的插入操作方法优化.docx

/zhyiwww/archive/2010/03/03/314427.htmlblob的插入操作方法优化 oracle环境的jdbc操作[方法1]先插入empty_blob(),在检索出刚插入的数据，更新blob插入代码? //获得数据库连接 ? ????Connection?con?=?ConnectionFactory.getConnection();? ????con.setAutoCommit(false);? ????Statement?st?=?con.createStatement();? ????//插入一个空对象empty_blob()? ????st.executeUpdate(insert?into?TESTBLOB?(ID,?NAME,?BLOBATTR)?values?(1,?thename,?empty_blob()));? ????//锁定数据行进行更新，注意“for?update”语句 ? ????ResultSet?rs?=?st.executeQuery(select?BLOBATTR?from?TESTBLOB?where?ID=1?for?update);? ????if?(rs.next())? ????{? ????????//得到java.sql.Blob对象后强制转换为oracle.sql.BLOB? ????????oracle.sql.BLOB?blob?=?(oracle.sql.BLOB)?rs.getBlob(BLOBATTR);? ????????OutputStream?outStream?=?blob.getBinaryOutputStream();? ????????//data是传入的byte数组，定义：byte[]?data? ????????outStream.write(data,?0,?data.length);? ????}? ????outStream.flush();? ????outStream.close();? ????mit();? ????con.close(); 注：以上代码来自网上。[方法2]和1相同，但是，我们不用两次操作了，因为我们可以直接用byte[]来替代blob,如： PreparedStatement pstmt = null; StringBuffer sb = new StringBuffer(800); sb.append(INSERT INTO ARTICAL); sb.append((); sb.append(ARTICAL_ID); sb.append(,); sb.append(CATEGORY_ID); sb.append(,); sb.append(ARTICAL_TITLE); sb.append(,); sb.append(ARTICAL_TAGS); sb.append(,); sb.append(ARTICAL_INTO_DATE); sb.append(,); sb.append(ARTICAL_FILE_TYPE); sb.append(,); sb.append(ARTICAL_CONTENT); sb.append()); sb.append( ); sb.append(values); sb.append((); sb.append(?); sb.append(,); sb.append(?); sb.append(,); sb.append(?); sb.append(,); sb.append(?); sb.append(,); sb.append(?); sb.append(,); sb.append(?); sb.append(,);//??? ??? sb.append(empty_blob()); sb.append(?); sb.append()); try { pstmt = createPreparedStatement(sb.toString()); pstmt.setLong(1, artical.getArticalId()); pstmt.setLong(2, artical.getCategoryId()); pstmt.setString(3, artical.getTitle()); pstmt.setString(4, artical.getTags()); pstmt.setDate(5, new Date(System.currentTimeMillis())); pstmt.setString(6, artical.getFileType()); // 此处直接用数组 pstmt.setBytes(