为什么不能写入数据？

[hu1125]

数据表：create table bbs_Article
(
articleID int not null primary key,
articleTitle text null,
articleContent text null,
articleRe text null,
articleDate smalldatetime null,
rootID int null,
articleBoard int foreign key references bbs_Board(boardID)
)
GO
用c#编程：private void btnSubmit_Click(object sender, System.EventArgs e)
{
string articleTitle = this.txtTitle.Text;
string articleContent=this.txtContent.Text;
SqlConnection con = DB.createCon();
con.Open();
SqlCommand cmd1=new SqlCommand ("select articleID from bbs_Article order by articleID DESC",con);
int articleID=Convert.ToInt32 (cmd1.ExecuteScalar ())+1;
SqlCommand cmd = new SqlCommand ("insert into bbs_Article (articleID,articleTitle,articleContent,articleBoard,rootID)values('"+@articleID+"','"+@articleTitle+"','"+@articleContent+"','1,'"+@articleID+"')",con);
cmd.ExecuteNonQuery();
con.Close();
Response.Redirect ("showLuntan.aspx");

}
请问rootID字段为什么不能写入数据啊？

[gc_ding]

rootID字段与articleID用同一个变量@articleID？
不太懂，帮顶。。。

[dawugui]

articleDate smalldatetime null,
articleRe text null,

插入时将上面两个字段附上NULL,试试.