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<h1 class="refname">pg_lo_read</h1>
<p class="verinfo">(PHP 4 >= 4.2.0, PHP 5, PHP 7)</p><p class="refpurpose"><span class="refname">pg_lo_read</span> — <span class="dc-title">Read a large object</span></p>
</div>
<div class="refsect1 description" id="refsect1-function.pg-lo-read-description">
<h3 class="title">Description</h3>
<div class="methodsynopsis dc-description">
<span class="type">string</span> <span class="methodname"><strong>pg_lo_read</strong></span>
( <span class="methodparam"><span class="type">resource</span> <code class="parameter">$large_object</code></span>
[, <span class="methodparam"><span class="type">int</span> <code class="parameter">$len</code><span class="initializer"> = 8192</span></span>
] )</div>
<p class="para rdfs-comment">
<span class="function"><strong>pg_lo_read()</strong></span> reads at most
<code class="parameter">len</code> bytes from a large object and
returns it as a <span class="type"><a href="language.types.string.html" class="type string">string</a></span>.
</p>
<p class="para">
To use the large object interface, it is necessary to
enclose it within a transaction block.
</p>
<blockquote class="note"><p><strong class="note">Note</strong>:
<p class="para">
This function used to be called <span class="function"><strong>pg_loread()</strong></span>.
</p>
</p></blockquote>
</div>
<div class="refsect1 parameters" id="refsect1-function.pg-lo-read-parameters">
<h3 class="title">Parameters</h3>
<p class="para">
<dl>
<dt>
<code class="parameter">large_object</code></dt>
<dd>
<p class="para">
PostgreSQL large object (LOB) resource, returned by <span class="function"><a href="function.pg-lo-open.html" class="function">pg_lo_open()</a></span>.
</p>
</dd>
<dt>
<code class="parameter">len</code></dt>
<dd>
<p class="para">
An optional maximum number of bytes to return.
</p>
</dd>
</dl>
</p>
</div>
<div class="refsect1 returnvalues" id="refsect1-function.pg-lo-read-returnvalues">
<h3 class="title">Return Values</h3>
<p class="para">
A <span class="type"><a href="language.types.string.html" class="type string">string</a></span> containing <code class="parameter">len</code> bytes from the
large object, or <strong><code>FALSE</code></strong> on error.
</p>
</div>
<div class="refsect1 examples" id="refsect1-function.pg-lo-read-examples">
<h3 class="title">Examples</h3>
<p class="para">
<div class="example" id="example-2573">
<p><strong>Example #1 <span class="function"><strong>pg_lo_read()</strong></span> example</strong></p>
<div class="example-contents">
<div class="phpcode"><code><span style="color: #000000">
<span style="color: #0000BB"><?php<br /> $doc_oid </span><span style="color: #007700">= </span><span style="color: #0000BB">189762345</span><span style="color: #007700">;<br /> </span><span style="color: #0000BB">$database </span><span style="color: #007700">= </span><span style="color: #0000BB">pg_connect</span><span style="color: #007700">(</span><span style="color: #DD0000">"dbname=jacarta"</span><span style="color: #007700">);<br /> </span><span style="color: #0000BB">pg_query</span><span style="color: #007700">(</span><span style="color: #0000BB">$database</span><span style="color: #007700">, </span><span style="color: #DD0000">"begin"</span><span style="color: #007700">);<br /> </span><span style="color: #0000BB">$handle </span><span style="color: #007700">= </span><span style="color: #0000BB">pg_lo_open</span><span style="color: #007700">(</span><span style="color: #0000BB">$database</span><span style="color: #007700">, </span><span style="color: #0000BB">$doc_oid</span><span style="color: #007700">, </span><span style="color: #DD0000">"r"</span><span style="color: #007700">);<br /> </span><span style="color: #0000BB">$data </span><span style="color: #007700">= </span><span style="color: #0000BB">pg_lo_read</span><span style="color: #007700">(</span><span style="color: #0000BB">$handle</span><span style="color: #007700">, </span><span style="color: #0000BB">50000</span><span style="color: #007700">);<br /> </span><span style="color: #0000BB">pg_query</span><span style="color: #007700">(</span><span style="color: #0000BB">$database</span><span style="color: #007700">, </span><span style="color: #DD0000">"commit"</span><span style="color: #007700">);<br /> echo </span><span style="color: #0000BB">$data</span><span style="color: #007700">;<br /></span><span style="color: #0000BB">?></span>
</span>
</code></div>
</div>
</div>
</p>
</div>
<div class="refsect1 seealso" id="refsect1-function.pg-lo-read-seealso">
<h3 class="title">See Also</h3>
<p class="para">
<ul class="simplelist">
<li class="member"><span class="function"><a href="function.pg-lo-read-all.html" class="function" rel="rdfs-seeAlso">pg_lo_read_all()</a> - Reads an entire large object and send straight to browser</span></li>
</ul>
</p>
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