<?xml version="1.0" encoding="UTF-8" standalone="no"?>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"><html xmlns="http://www.w3.org/1999/xhtml"><head><meta http-equiv="Content-Type" content="text/html; charset=UTF-8" /><title>Chapter 35. Large Objects</title><link rel="stylesheet" type="text/css" href="stylesheet.css" /><link rev="made" href="pgsql-docs@lists.postgresql.org" /><meta name="generator" content="DocBook XSL Stylesheets Vsnapshot" /><link rel="prev" href="libpq-example.html" title="34.21. Example Programs" /><link rel="next" href="lo-intro.html" title="35.1. Introduction" /></head><body><div xmlns="http://www.w3.org/TR/xhtml1/transitional" class="navheader"><table width="100%" summary="Navigation header"><tr><th colspan="5" align="center">Chapter 35. Large Objects</th></tr><tr><td width="10%" align="left"><a accesskey="p" href="libpq-example.html" title="34.21. Example Programs">Prev</a> </td><td width="10%" align="left"><a accesskey="u" href="client-interfaces.html" title="Part IV. Client Interfaces">Up</a></td><th width="60%" align="center">Part IV. Client Interfaces</th><td width="10%" align="right"><a accesskey="h" href="index.html" title="PostgreSQL 11.5 Documentation">Home</a></td><td width="10%" align="right"> <a accesskey="n" href="lo-intro.html" title="35.1. Introduction">Next</a></td></tr></table><hr></hr></div><div class="chapter" id="LARGEOBJECTS"><div class="titlepage"><div><div><h2 class="title">Chapter 35. Large Objects</h2></div></div></div><div class="toc"><p><strong>Table of Contents</strong></p><dl class="toc"><dt><span class="sect1"><a href="lo-intro.html">35.1. Introduction</a></span></dt><dt><span class="sect1"><a href="lo-implementation.html">35.2. Implementation Features</a></span></dt><dt><span class="sect1"><a href="lo-interfaces.html">35.3. Client Interfaces</a></span></dt><dd><dl><dt><span class="sect2"><a href="lo-interfaces.html#LO-CREATE">35.3.1. Creating a Large Object</a></span></dt><dt><span class="sect2"><a href="lo-interfaces.html#LO-IMPORT">35.3.2. Importing a Large Object</a></span></dt><dt><span class="sect2"><a href="lo-interfaces.html#LO-EXPORT">35.3.3. Exporting a Large Object</a></span></dt><dt><span class="sect2"><a href="lo-interfaces.html#LO-OPEN">35.3.4. Opening an Existing Large Object</a></span></dt><dt><span class="sect2"><a href="lo-interfaces.html#LO-WRITE">35.3.5. Writing Data to a Large Object</a></span></dt><dt><span class="sect2"><a href="lo-interfaces.html#LO-READ">35.3.6. Reading Data from a Large Object</a></span></dt><dt><span class="sect2"><a href="lo-interfaces.html#LO-SEEK">35.3.7. Seeking in a Large Object</a></span></dt><dt><span class="sect2"><a href="lo-interfaces.html#LO-TELL">35.3.8. Obtaining the Seek Position of a Large Object</a></span></dt><dt><span class="sect2"><a href="lo-interfaces.html#LO-TRUNCATE">35.3.9. Truncating a Large Object</a></span></dt><dt><span class="sect2"><a href="lo-interfaces.html#LO-CLOSE">35.3.10. Closing a Large Object Descriptor</a></span></dt><dt><span class="sect2"><a href="lo-interfaces.html#LO-UNLINK">35.3.11. Removing a Large Object</a></span></dt></dl></dd><dt><span class="sect1"><a href="lo-funcs.html">35.4. Server-side Functions</a></span></dt><dt><span class="sect1"><a href="lo-examplesect.html">35.5. Example Program</a></span></dt></dl></div><a id="id-1.7.4.2" class="indexterm"></a><a id="id-1.7.4.3" class="indexterm"></a><p>
<span class="productname">PostgreSQL</span> has a <em class="firstterm">large object</em>
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.
</p><p>
This chapter describes the implementation and the programming and
query language interfaces to <span class="productname">PostgreSQL</span>
large object data. We use the <span class="application">libpq</span> C
library for the examples in this chapter, but most programming
interfaces native to <span class="productname">PostgreSQL</span> support
equivalent functionality. Other interfaces might use the large
object interface internally to provide generic support for large
values. This is not described here.
</p></div><div class="navfooter"><hr /><table width="100%" summary="Navigation footer"><tr><td width="40%" align="left"><a accesskey="p" href="libpq-example.html">Prev</a> </td><td width="20%" align="center"><a accesskey="u" href="client-interfaces.html">Up</a></td><td width="40%" align="right"> <a accesskey="n" href="lo-intro.html">Next</a></td></tr><tr><td width="40%" align="left" valign="top">34.21. Example Programs </td><td width="20%" align="center"><a accesskey="h" href="index.html">Home</a></td><td width="40%" align="right" valign="top"> 35.1. Introduction</td></tr></table></div></body></html>
