Small BLOBs
SMALLBLOBs are encoded into Strings before being stored and are mapped to VARCHAR2(4000) rather than BLOB. Because of the size limitation of 4,000 characters, this option is inflexible and should be used with caution. Your code should be prepared to handle the possible exception that is thrown if the size of the attribute grows beyond what can be encoded into 4,000 characters.
這是否有幫助?