ODAC讀寫BLOB

var
tf:TBlob;
ts:TMemoryStream;

/////显示原始上传图像
        DataModule1.OraQuery1.SQL.Clear;
        DataModule1.OraQuery1.SQL.Add('select tp from base  where id='+QuotedStr(RzDBEdit2.Text));
        DataModule1.OraQuery1.Open;

         if (not DataModule1.OraQuery1.Eof) then
         begin
           DataModule1.OraQuery1.First ;
           tf:=DataModule1.OraQuery1.GetBlob('tp' ) ;
           if tf.Size>0 then
            begin
              tf.SaveToFile( 'c:\1.jpg');
             Image1.Picture.LoadFromFile('c:\1.jpg')  ;

             end;
          end;
//写数据：
DataModule1.OraSQL1.SQL.Clear ;
DataModule1.OraSQL1.SQL.Add('insert into sample(XM,TP)  values (:XM,EMPTY_BLOB()) returning TP into :TP')  ;
//DataModule1.OraSQL1.SQL.Add('update sample set TP=EMPTY_BLOB() where XM=:XM returning TP into :TP')  ;
DataModule1.OraSQL1.Prepare ;
DataModule1.OraSQL1.ParamByName('XM').AsString := '123'
DataModule1.OraSQL1.ParamByName('TP').ParamType :=ptInput;
ts:=TMemoryStream.Create ;
if tf.Size>0 then  tf.SaveToStream(ts)  ;
DataModule1.OraSQL1.ParamByName('TP').AsOraBlob.LoadFromStream (ts);
ts.Free ;
DataModule1.OraSQL1.Execute ;