winform实现ＳＱＬＳＥＲＶＥＲ存储图片

Question

private SqlConnection mycnn=null;
//保存图片到数据库
 mycnn=new SqlConnection(@"server=zhurongj;database=my1;Trusted_connection=yes");
mycnn.Open();
 SqlCommand mycmd=new SqlCommand("update picture set picture=@a where ID=1",mycnn);FileStream mystream=new FileStream("f:\\1.jpg",FileMode.Open,FileAccess.Read);
long len=mystream.Length;mycmd.Parameters.Add("@a",SqlDbType.Image,(int)len,"picture");
mycmd.Parameters["@a"].Direction=System.Data.ParameterDirection.Input;
           
byte []box=new byte[len]; 
mystream.Read(box,0,(int)len);mycmd.Parameters["@a"].Value=box;//更新
mycmd.ExecuteNonQuery();
MessageBox.Show("ok");
mystream.Close();
mycnn.Close();

Answer 1

"update picture set picture=@a where ID='1'",

Answer 2

private void btInsert_Click(object sender, EventArgs e)
        {
            conn.Open();
            OracleCommand mycmd=new OracleCommand("update JPB set PHOTO=@a where ID=123",conn);            FileStream mystream=new FileStream("f:\\1.ico",FileMode.Open,FileAccess.Read);
            long len=mystream.Length;            mycmd.Parameters.Add("@a",OracleType.Blob,(int)len,"PHOTO");
            mycmd.Parameters["@a"].Direction=System.Data.ParameterDirection.Input;
                
            byte []box=new byte[len];  
            mystream.Read(box,0,(int)len);            mycmd.Parameters["@a"].Value=box;            //更新
            mycmd.ExecuteNonQuery();
            MessageBox.Show("ok");
            mystream.Close();
            conn.Close();        }
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