Data Source Initialization OLE DB Property – «blob_send_mode»
Name:
blob_send_mode
Type:
VT_BSTR
R/W:
R/W
Default:
EMPTY
IBProvider:
5.36
This property defines how provider can send BLOB to server. An empty value or one value from the following list is allowed:
Value | Description |
std |
A standard method with using a handle for passing BLOB data. It is a default mode for Yaffil, InterBase and Firebird v0.9-v2.5.0. |
varchar |
Provider can use VARCHAR-strings for passing BLOB data. It is a default mode for Firebird v2.5.1+. There are some restrictions — see below. |
Restrictions on passing BLOBs as VARCHAR strings:
- The maximum length of BLOB is limited by the capacity of VARCHAR values. For example, for FB4 it is 32765 bytes. If the size of the BLOB data exceeds this limit, the provider will automatically use the standard method of passing BLOBs through the handle.
- Firebird 2.5.x limits the total size of the parameter value buffer to 65535 bytes.
- When provider works with Firebird via fbclient.dll, the total size of the buffer with values is limited to 65535 bytes.