Microsoft OLE DB 2.0 Programmers Reference and Data Access SDK (Microsoft Professional Editions)
| OLE DB Programmer's Reference |
The tables in this section describe most additional conversions. They use the following symbols:
- S = A safe conversion is possible.
- T = Conversion with truncation of nonsignificant digits is possible.
- E = An error due to truncation of significant digits is possible.
- – = The conversion is not generally supported.
| To → From ↓ | I1 | I2 | I4 | I8 | UI1 |
|---|---|---|---|---|---|
| I1 | S | S | S | S | S, E |
| I2 | S, E | S | S | S | S, E |
| I4 | S, E | S, E | S | S | S, E |
| I8 | - | - | - | S | - |
| UI1 | S, E | S | S | S | S |
| UI2 | S, E | S, E | S | S | S, E |
| UI4 | S, E | S, E | S, E | S | S, E |
| UI8 | - | - | - | S, E | - |
| R4 | S, T, E | S, T, E | S, T | S, T | S, T, E |
| R8 | S, T, E | S, T, E | S, T, E | S, T | S, T, E |
| CY | S, T, E | S, T, E | S, T, E | S, T | S, T, E |
| DEC | S, T, E | S, T, E | S, T, E | S, T, E | S, T, E |
| NUM | S, T, E | S, T, E | S, T, E | S, T, E | S, T, E |
| BOOL | S | S | S | S | S |
| DATE | S | S | S | S | S |
| DBDATE | – | – | – | – | – |
| DBTIME | – | – | – | – | – |
| DBTIMESTAMP | – | – | – | – | – |
| FILETIME | – | – | – | S, E | – |
| BYTES | S, E | S, E | S, E | S, E | S, E |
| BSTR | S, T, E | S, T, E | S, T, E | S, T, E | S, T, E |
| STR | S, T, E | S, T, E | S, T, E | S, T, E | S, T, E |
| WSTR | S, T, E | S, T, E | S, T, E | S, T, E | S, T, E |
| VARIANT | S, T, E | S | S | S, T, E | S, T, E |
| DISP | – | – | – | – | – |
| UNK | – | – | – | – | – |
| GUID | – | – | – | – | – |
| ERROR | – | – | – | – | – |
| PROPVARIANT | S, T, E | S | S | S | S |
| To → From ↓ | UI2 | UI4 | UI8 | R4 | R8 |
|---|---|---|---|---|---|
| I1 | S, E | S, E | S, E | S | S |
| I2 | S, E | S, E | S, E | S | S |
| I4 | S, E | S, E | S, E | S | S |
| I8 | - | - | S, E | - | - |
| UI1 | S | S | S | S | S |
| UI2 | S | S | S | S | S |
| UI4 | S, E | S | S | S, E | S |
| UI8 | - | - | S | - | - |
| R4 | S, T, E | S, T, E | S, T, E | S | S |
| R8 | S, T, E | S, T, E | S, T, E | S, E | S |
| CY | S, T, E | S, T, E | S, T, E | S, E | S, E |
| DEC | S, T, E | S, T, E | S, T, E | S, E | S, E |
| NUM | S, T, E | S, T, E | S, T, E | S, E | S, E |
| BOOL | S | S | S | S | S |
| DATE | S | S | S | S | S |
| DBDATE | – | – | – | – | – |
| DBTIME | – | – | – | – | – |
| DBTIMESTAMP | – | – | – | – | – |
| FILETIME | – | – | S, E | – | – |
| BYTES | S, E | S, E | S, E | S, E | S, E |
| BSTR | S, T, E | S, T, E | S, T, E | S, T, E | S, T, E |
| STR | S, T, E | S, T, E | S, T, E | S, T, E | S, T, E |
| WSTR | S, T, E | S, T, E | S, T, E | S, T, E | S, T, E |
| VARIANT | S, T, E | S, T, E | S, T, E | S | S |
| DISP | – | – | – | – | – |
| UNK | – | – | – | – | – |
| GUID | – | – | – | – | – |
| ERROR | – | – | – | – | – |
| PROPVARIANT | S | S | S | S | S |
| To → From ↓ | CY | DEC | NUM | BOOL | DATE |
|---|---|---|---|---|---|
| I1 | S | S | S | S | S |
| I2 | S | S | S | S | S |
| I4 | S | S | S | S | S |
| I8 | - | - | - | - | - |
| UI1 | S | S | S | S | S |
| UI2 | S | S | S | S | S |
| UI4 | S | S | S | S | S |
| UI8 | - | - | - | - | - |
| R4 | S, T | S | S | S | S |
| R8 | S, T | S | S | S | S |
| CY | S | S | S | S | - |
| DEC | S, E | S | S | S | - |
| NUM | S, E | S, T, E | S | S | - |
| BOOL | S | S | S | S | S |
| DATE | S | S | S | S | S |
| DBDATE | – | – | – | – | S |
| DBTIME | – | – | – | – | S |
| DBTIMESTAMP | – | – | – | – | S, T |
| FILETIME | – | – | – | – | S, T |
| BYTES | S, E | S, E | S, E | S, E | - |
| BSTR | S, T, E | S, T, E | S, T, E | S, E | S, T, E |
| STR | S, T, E | S, T, E | S, T, E | S, E | S, T, E |
| WSTR | S, T, E | S, T, E | S, T, E | S, E | S, T, E |
| VARIANT | S | S | S, T, E | S | S |
| DISP | – | – | – | – | – |
| UNK | – | – | – | – | – |
| GUID | – | – | – | – | – |
| ERROR | – | – | – | – | – |
| PROPVARIANT | S | S | S, T, E | S | S |
| To → From ↓ | DBDATE | DBTIME | DBTIME STAMP | FILE TIME | BYTES |
|---|---|---|---|---|---|
| I1 | – | – | – | – | - |
| I2 | – | – | – | – | S, E |
| I4 | – | – | – | – | S, E |
| I8 | – | – | – | S, E | - |
| UI1 | – | – | – | – | - |
| UI2 | – | – | – | – | S, E |
| UI4 | – | – | – | – | S, E |
| UI8 | – | – | – | S, E | - |
| R4 | – | – | – | – | S, E |
| R8 | – | – | – | – | S, E |
| CY | – | – | – | – | S, E |
| DEC | – | – | – | – | S, E |
| NUM | – | – | – | – | S, E |
| BOOL | – | – | – | – | S |
| DATE | S, T, E | S, T | S, T, E | S, T, E | S, E |
| DBDATE | S | S | S | S | S, E |
| DBTIME | S | S | S | S | S, E |
| DBTIMESTAMP | S, T | S, T | S | S, T | S, E |
| FILETIME | S, T, E | S, T, E | S, T, E | S | S, E |
| BYTES | S, E | – | S | S, E | S, E |
| BSTR | S, T, E | S, T, E | S, T, E | S, T, E | S, E |
| STR | S, T, E | S, T, E | S, T, E | S, T, E | S, E |
| WSTR | S, T, E | S, T, E | S, T, E | S, T, E | S, E |
| VARIANT | S, T, E | S, T, E | S, T, E | S, T, E | S, T, E |
| DISP | – | – | – | – | S, E |
| UNK | – | – | – | – | S, E |
| GUID | – | – | – | – | - |
| ERROR | – | – | – | – | – |
| PROPVARIANT | S, T, E | S, T, E | S, T, E | S, T, E | S |
| HCHAPTER | - | - | - | - | S |
| To → From ↓ | BSTR | STR | WSTR | VARIANT | DISP |
|---|---|---|---|---|---|
| I1 | S, E | S, E | S, E | S | – |
| I2 | S, E | S, E | S, E | S | – |
| I4 | S, E | S, E | S, E | S | – |
| I8 | S, E | S, E | S, E | S | – |
| UI1 | S, E | S, E | S, E | S | – |
| UI2 | S, E | S, E | S, E | – | – |
| UI4 | S, E | S, E | S, E | S | – |
| UI8 | S, E | S, E | S, E | S | – |
| R4 | S, E | S, T, E | S, T, E | S | – |
| R8 | S, E | S, T, E | S, T, E | S | – |
| CY | S, E | S, T, E | S, T, E | S | – |
| DEC | S, E | S, T, E | S, T, E | S | – |
| NUM | S, E | S, T, E | S, T, E | – | – |
| BOOL | S, E | S, E | S, E | S | – |
| DATE | S, E | S, T, E | S, T, E | S | – |
| DBDATE | S, E | S, T, E | S, T, E | S | – |
| DBTIME | S, E | S, T, E | S, T, E | S | – |
| DBTIMESTAMP | S, E | S, T, E | S, T, E | S | – |
| FILETIME | S, E | S, T, E | S, T, E | S | – |
| BYTES | S, E | S, E | S, E | – | S, E |
| BSTR | S | S, T | S, T | S | |
| STR | S | S, T | S, T | S | – |
| WSTR | S | S, T | S, T | S | – |
| VARIANT | S, T, E | S, T, E | S, T, E | S | S |
| DISP | – | – | – | S | S |
| UNK | – | – | – | S | – |
| GUID | S, E | S, E | S, E | S | – |
| ERROR | – | – | – | S | – |
| PROPVARIANT | S, T, E | S, T, E | S, T, E | S | S |
| HCHAPTER | - | - | S | - | - |
| To → From ↓ | UNK | GUID | ERROR | PROPVARIANT | HCHAPTER |
|---|---|---|---|---|---|
| I1 | – | – | – | - | - |
| I2 | – | – | – | S | - |
| I4 | – | – | – | S | - |
| I8 | – | – | – | S | - |
| UI1 | – | – | – | S | - |
| UI2 | – | – | – | S | - |
| UI4 | – | – | – | S | - |
| UI8 | – | – | – | S | - |
| R4 | – | – | – | S | - |
| R8 | – | – | – | S | - |
| CY | – | – | – | S | - |
| DEC | – | – | – | - | - |
| NUM | – | – | – | - | - |
| BOOL | – | – | – | S | - |
| DATE | – | – | – | S | - |
| DBDATE | – | – | – | - | - |
| DBTIME | – | – | – | - | - |
| DBTIMESTAMP | – | – | – | - | - |
| FILETIME | – | – | – | S | - |
| BYTES | S, E | S, E | – | S | S |
| BSTR | – | S, E | – | S | - |
| STR | S, E | S, E | – | S | - |
| WSTR | S, E | S, E | – | S | S |
| VARIANT | S | S, T, E | S | S | - |
| DISP | S | – | – | S | - |
| UNK | S | – | – | - | - |
| GUID | – | S | – | S | - |
| ERROR | – | – | S | - | - |
| PROPVARIANT | S | S | S | S | - |
1998-2001 Microsoft Corporation. All rights reserved.