如何使用JDBC更新Oracle Clob [英] How to update Oracle Clob by using JDBC

问题描述

正常方式如下：

  pStmt = conn.prepareStatement（SELECT DETAILS FROM PROGRAM_HISTORY WHERE id = 12） ; 
 rset = pStmt.executeQuery（）; 
 Clob detailsClob = rset.getClob（1）; 
 Writer writer = adapter.getCharacterOutputStream（detailsClob）; 
 writer.write（add more details）; 
 
 pStmt = conn.prepareStatement（UPDATE PROGRAM_HISTORY SET DETAILS =？WHERE ID = 12）; 
 pStmt.setClob（1，detailsClob）; 
 pStmt.execute（）; 
  

这有点复杂，是任何方式，我不需要先读，然后更新。就像更新varchar。

解决方案

不知道为什么你称之为正常的方式， / p>

更新之前不需要任何检索数据。

  String value =这么久，感谢所有的鱼; 
 StringReader reader = new StringReader（value）; 
 pStmt = conn.prepareStatement（UPDATE PROGRAM_HISTORY SET DETAILS =？WHERE ID = 12）; 
 pStmt.setCharacterStream（1，reader，value.length（）; 
 pStmt.executeUpdate（）; 
  

Normal way looks like this:

    pStmt = conn.prepareStatement("SELECT DETAILS FROM PROGRAM_HISTORY WHERE id = 12");
    rset = pStmt.executeQuery();
    Clob detailsClob= rset.getClob(1);
    Writer writer = adapter.getCharacterOutputStream(detailsClob);
    writer.write("add more details"); 

    pStmt = conn.prepareStatement("UPDATE PROGRAM_HISTORY SET DETAILS = ? WHERE ID = 12");
    pStmt.setClob(1, detailsClob);
    pStmt.execute();

This is a little bit complicated, is any way that I don't need read first then update it. just like update varchar.

解决方案

Not sure why you call that the "normal" way, but the following works for me.

It doesn't require any retrieval of the data before updating it.

String value = "So long and thanks for all the fish";
StringReader reader = new StringReader(value);
pStmt = conn.prepareStatement("UPDATE PROGRAM_HISTORY SET DETAILS = ? WHERE ID = 12");
pStmt.setCharacterStream(1, reader, value.length();
pStmt.executeUpdate();

这篇关于如何使用JDBC更新Oracle Clob的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！