How to operate lob by using DBMS_LOB in 11g

–Test version: 11.1.0.6
–The DBMS_LOB package provides subprograms to operate on BLOBs, CLOBs, NCLOBs, BFILEs, and temporary LOBs.
–DBMS_LOB can read and modify BLOBs, CLOBs, and NCLOBs;it provides read-only operations for BFILEs
Temporary LOB
-Stored in temporary tablespaces, deleted at the end of the session by default
Internal LOB
-LOB columns are defined in a table
-Use DML to initialize or populate [...]