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<a href="intro.html"><h2>SQLite C Interface</h2></a>
<h2>Run-time Limits</h2>
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<blockquote><pre>
int sqlite3_limit(sqlite3*, int id, int newVal);
</pre></blockquote>
<p>
This interface allows the size of various constructs to be limited
on a connection by connection basis. The first parameter is the
<a href="../c3ref/sqlite3.html">database connection</a> whose limit is to be set or queried. The
second parameter is one of the <a href="../c3ref/c_limit_attached.html">limit categories</a> that define a
class of constructs to be size limited. The third parameter is the
new limit for that construct.</p>
<p>If the new limit is a negative number, the limit is unchanged.
For each limit category SQLITE_LIMIT_<i>NAME</i> there is a
<a href="../limits.html">hard upper bound</a>
set at compile-time by a C preprocessor macro called
<a href="../limits.html">SQLITE_MAX_<i>NAME</i></a>.
(The "_LIMIT_" in the name is changed to "_MAX_".)
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silently truncated to the hard upper bound.</p>
<p>Regardless of whether or not the limit was changed, the
<a href="../c3ref/limit.html">sqlite3_limit()</a> interface returns the prior value of the limit.
Hence, to find the current value of a limit without changing it,
simply invoke this interface with the third parameter set to -1.</p>
<p>Run-time limits are intended for use in applications that manage
both their own internal database and also databases that are controlled
by untrusted external sources. An example application might be a
web browser that has its own databases for storing history and
separate databases controlled by JavaScript applications downloaded
off the Internet. The internal databases can be given the
large, default limits. Databases managed by external sources can
be given much smaller limits designed to prevent a denial of service
attack. Developers might also want to use the <a href="../c3ref/set_authorizer.html">sqlite3_set_authorizer()</a>
interface to further control untrusted SQL. The size of the database
created by an untrusted script can be contained using the
<a href="../pragma.html#pragma_max_page_count">max_page_count</a> <a href="../pragma.html#syntax">PRAGMA</a>.</p>
<p>New run-time limit categories may be added in future releases.
</p><p>See also lists of
<a href="objlist.html">Objects</a>,
<a href="constlist.html">Constants</a>, and
<a href="funclist.html">Functions</a>.</p>
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