sql数据库varchar和nvarchar坑

问题描述：将部分符号，例如： 详细摘要或全文−侯春曰-20150531094315438，里的 - 存进varchar字段时，会因为识别不了变成?.

因此，为了兼容更多的字符，不确定数据来源的情况下还是用nvarchar比较保险.

编辑时要加 insert into a(NAME) values (N'呵呵');

StringBuffer sql = new StringBuffer();
sql.append(" insert into files(id,md5key,filename,filepath,created_time,status,"
+ "filetype,url,download_time,pdf_path,swf_path,pdf_finish_time,swf_finish_time,error_remark,ext_attr,filesize,total_pages) "
+ "values (?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?) ");

// 产生唯一标识，uuid并去除‘-’号
String id = UUID.randomUUID().toString().replace("-", "");
PooledConnection conn = null;
PreparedStatement statement = null;
ResultSet resultSet = null;
PreparedStatement preStatement = null;
try {
conn = DBManager.getConnection();
statement = conn.prepareStatement(sql.toString());
statement.setString(1, id);
statement.setString(2, filePreview.getMd5Key());
statement.setNString(3, filePreview.getFilename());
<strong><span style="background-color: rgb(255, 204, 102);">statement.setNString(4, filePreview.getFilepath());</span></strong>
statement.setTimestamp(5, new Timestamp(filePreview.getCreateTime()
.getTime()));
statement.setString(6, filePreview.getStatus());
statement.setString(7, filePreview.getFiletype());
statement.setNString(8, filePreview.getUrl());