bool flush(int flag);
OCI-Lob->flush() actually writes data to the server.
By default, resources are not freed, but using flag
OCI_LOB_BUFFER_FREE you can do it explicitly.
Be sure you know what you're doing - next read/write operation to the
same part of LOB will involve a round-trip to the server and initialize
new buffer resources. It is recommended to use
OCI_LOB_BUFFER_FREE flag only when you are not
going to work with the LOB anymore.
TRUE on success or
FALSE on failure.
FALSE if buffering was not enabled or an error occurred.