C ++ Builder/Delphi access the Blob field of Oracle through ADO

Today, the Report Group reported an error when reading the Blob field of Oracle using ADO in CB5, so I tried it. The error message is "unsupported data type ".
I tried Delphi7 again.
I think the BCB/Delphi ADO is encapsulated. Is there a problem with encapsulation?
So I ran to VB and wrote a Demo, and it succeeded ~ It seems that it is encapsulation.
It seems that you only have to use OLE to directly manipulate ADO, write a code segment, and try again.
The BCB code is as follows: 1 void _ fastcall TForm1: Button1Click (TObject * Sender)
2 {
3 const AnsiString SQL = "SELECT * FROM Table WHERE ROWNUM <= 1 ";
4
5 Variant Conn;
6 Variant ResultSet;
7 Variant ResultField;
8 Variant Size, Value;
9
10 Conn = Variant: CreateObject ("adodb. connection ");
11 Conn. OlePropertySet ("Provider", "OraOLEDB. Oracle ");
12 Conn. OleFunction ("Open", "Database", "UserName", "Password ");
13
14 ResultSet = Variant: CreateObject ("adodb. recordset ");
15 ResultSet. OleFunction ("Open", SQL, Conn, 0, 1 );
16 ResultField = ResultSet. OlePropertyGet ("Fields", "FieldNameOrIndex ");
17 Size = ResultField. OlePropertyGet ("ActualSize ");
18 Value = ResultField. OleFunction ("GetChunk", Size );
19
20 void * Data = NULL;
21 SafeArrayAccessData (Value. parray, & Data );
22 try
23 {
24 TFileStream * Stream = new TFileStream ("C: \ blob.txt", fmCreate );
25 try
26 {
27 Stream-> Write (Data, Size );
28} _ finally {
29 delete Stream;
30}
31} _ finally {
32 SafeArrayUnaccessData (Value. parray );
33}
34}