(PHP 5, PECL OCI8 >= 1.1.0)
OCI-Lob::flush — Flushes/writes buffer of the LOB to the server
$flag
  ] )OCI-Lob::flush() actually writes data to the server.
flag
       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.
      
   Returns TRUE on success or FALSE on failure.
  
   Returns FALSE if buffering was not enabled or an error occurred.