12 Persistent LOBs: Advanced DDL

This chapter describes advanced LOB DDL features to make your application more scalable.

Note:

Unless otherwise stated, all features in this chapter apply to both SecureFile and Basicfile LOBs. However, Oracle strongly recommends SecureFiles for storing and managing LOBs.

• Creating a New LOB Column
  You can provide the LOB storage characteristics when creating a LOB column using the CREATE TABLE statement or the ALTER TABLE ADD COLUMN statement.
• Altering an Existing LOB Column
  You can use the ALTER TABLE statement to change the storage characteristics of a LOB column.
• Creating an Index on LOB Column
  The contents of a LOB are often specific to the application, so an index on the LOB column will usually deal with application logic. You can create a function-based or a domain index on a LOB column to improve the performance of queries accessing data stored in LOB columns. You cannot build a B-tree or bitmap index on a LOB column.
• LOBs in Partitioned Tables
  Partitioning can simplify the manageability of large database objects. This section discusses various aspects of LOBs in partitioned tables.
• LOBs in Index Organized Tables
  Index Organized Tables (IOTs) support LOB and BFILE columns.