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,我不需要先读取然后更新它。就像更新varchar一样。
答案 0 :(得分:6)
不确定为什么你称之为“正常”方式,但以下方法适用于我。
在更新之前不需要检索任何数据。
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();