Chapter 33. Large Objects

   Table of Contents

   33.1. Introduction
   33.2. Implementation Features
   33.3. Client Interfaces

        33.3.1. Creating a Large Object
        33.3.2. Importing a Large Object
        33.3.3. Exporting a Large Object
        33.3.4. Opening an Existing Large Object
        33.3.5. Writing Data to a Large Object
        33.3.6. Reading Data from a Large Object
        33.3.7. Seeking in a Large Object
        33.3.8. Obtaining the Seek Position of a Large Object
        33.3.9. Truncating a Large Object
        33.3.10. Closing a Large Object Descriptor
        33.3.11. Removing a Large Object

   33.4. Server-Side Functions
   33.5. Example Program

   PostgreSQL has a large object facility, which provides stream-style
   access to user data that is stored in a special large-object structure.
   Streaming access is useful when working with data values that are too
   large to manipulate conveniently as a whole.

   This chapter describes the implementation and the programming and query
   language interfaces to PostgreSQL large object data. We use the libpq C
   library for the examples in this chapter, but most programming
   interfaces native to PostgreSQL support equivalent functionality. Other
   interfaces might use the large object interface internally to provide
   generic support for large values. This is not described here.