Chapter 42. Large Objects

Table of Contents

Historical Note

Inversion Large Objects

Large Object Interfaces

Built in registered functions

Accessing Large Objects from LIBPQ

Sample Program

In Postgres, data values are stored in tuples and individual tuples cannot span data pages. Since the size of a data page is 8192 bytes, the upper limit on the size of a data value is relatively low. To support the storage of larger atomic values, Postgres provides a large object interface. This interface provides file oriented access to user data that has been declared to be a large type. This section describes the implementation and the programmatic and query language interfaces to Postgres large object data.