(PHP 5, PECL OCI8 >= 1.1.0)
OCI-Lob->read — Reads part of the large object
Reads length bytes from the current position of LOB's internal pointer.
Reading stops when length bytes have been read or end of the large object is reached. Internal pointer of the large object will be shifted on the amount of bytes read.
The length of data to read, in bytes.
Returns the contents as a string, 或者在失败时返回 FALSE.