21.6 DBMS_LOB Subprograms Used with DBFS

You should note that some changes have been made to the DBMS_LOB subprograms over time.

Table 21-2 summarizes changes made to PL/SQL package DBMS_LOB subprograms.

Be aware that some of the DBMS_LOB operations that existed before Oracle Database 11g Release 2 throw an exception error if the LOB is a DBFS link. To remedy this problem, modify your applications to explicitly replace the DBFS link with a LOB by calling the DBMS_LOB.COPY_FROM_LINK procedure before they make these calls. When the call completes, then the application can move the updated LOB back to DBFS using the DBMS_LOB.MOVE_TO_DBFS_LINK procedure, if necessary.

Other DBMS_LOB operations that existed before Oracle Database 11g Release 2 work transparently if the DBFS Link is in a file system that supports streaming. Note that these operations fail if streaming is either not supported or disabled.

Table 21-2 DBMS_LOB Subprograms

Subprogram Description

COPY_DBFS_LINK

Copies an existing DBFS link into a new LOB

COPY_FROM_DBFS_LINK

Copies the specified LOB data from DBFS HSM Store into the database

DBFS_LINK_GENERATE_PATHNAME

Returns a unique file path name for creating a DBFS Link

GET_DBFS_LINK

Returns the DBFS path name for a LOB

GET_DBFS_LINK_STATE

Returns the linking state of a LOB

MOVE_TO_DBFS_LINK

Moves the specified LOB data from the database into DBFS HSM Store

SET_DBFS_LINK

Links a LOB with a DBFS path name