Я делал так (для маленьких текстовых файлов меньших 1К):

procedure TMainF.ToBaseBClick(Sender: TObject);
var
MS:tMemoryStream;
bsize:longint;
i:integer;
buf:array[1..1024]of byte;
begin
MS:=tMemoryStream.Create;
InsQ.Parameters.ParamByName('Name').Value:=FirmE.Text;
InsQ.Parameters.ParamByName('FileName').Value:=FromFE.Text;
if MainFS = nil then
MainFS:=tFileStream.Create(FromFE.Text,fmOpenRead);
repeat
bsize:=MainFS.Read(buf,SizeOf(buf));
MS.Write(buf,bsize);
until bsize <> SizeOf(buf);
tParameter(InsQ.Parameters.ParamByName('Content')).LoadFromStream(MS, ftBlob);
InsQ.ExecSQL;
MS.Free;
i:=SelQ.Fields.FieldByName('id').AsInteger;
SelQ.Active:=false;
SelQ.Active:=true;
SelQ.Locate('id',i,[]);
end;

InsQ - tADOQuery