(PHP 5, PHP 7, PECL OCI8 >= 1.1.0)
OCI-Lob::truncate — Truncates large object
$length = 0
] ) : boolTruncates the LOB.
length
If provided, this method will truncate the LOB to
length bytes. Otherwise, it will completely
purge the LOB.
成功时返回 TRUE， 或者在失败时返回 FALSE。