As we came across the four LOB data types in Oracle, LOB structure can be split into its "What" and "Where" components. While LOB value answers to the "What' query, the LOB locator corresponds to the "Where" part. Together, they both make a complete structure of an LOB. Let us understand the LOB components.
The LOB value is the actual large file to be loaded in the database. The LOB locator points to the location of this file on the system. It can be thought of as a pointer which references the system location of a file. A LOB locator is always stored inline with the table row irrespective of where the LOB value is stored. During insertion of the LOB data, the LOB column necessarily has the LOB locator component which points to the actual location of the LOB value in the system. The LOB value is always stored in the LOB segment which can be placed in the same or different tablespace.
For an internal LOB, the LOB segment has both the...