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<li><a href="ne/">!=</a>
<li><a href="lt/"><</a>
<li><a href="le/"><=</a>
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<h1><i class="glyphicon glyphicon-leaf"></i> <code class="mod">lektor.db.</code><code class="obj">Expression</code></h1>
<ul class=page-meta>
</ul>
<p>Expressions are used to filter down <a href="../query/" class="ref">Query</a> objects. They
can be passed to the <a href="../query/filter/" class="ref">filter</a> function in particular.</p>
<p>The most basic expression is created by accessing the <a href="../f/" class="ref">F</a> object
which will return an expression that points to a field. Further manipulation
of it can create more expressive expressions. <code>F.name</code> literally just means
that a field by that name exists and is set to a value.</p>
<p>The query syntax is mostly the same in Python as well as in the Jinja 2
templates, the main difference are <a href="and/" class="ref">and</a> and <a href="or/" class="ref">or</a>.</p>
<h2 id="example">Example</h2><div class="hll"><pre><span></span><span class="gp">>>> </span><span class="n">p</span><span class="o">.</span><span class="n">children</span><span class="o">.</span><span class="n">filter</span><span class="p">((</span><span class="n">F</span><span class="o">.</span><span class="n">name</span> <span class="o">==</span> <span class="s1">'foo'</span><span class="p">)</span> <span class="o">|</span> <span class="p">(</span><span class="n">F</span><span class="o">.</span><span class="n">name</span> <span class="o">==</span> <span class="s1">'bar'</span><span class="p">))</span><span class="o">.</span><span class="n">all</span><span class="p">()</span>
<span class="go">[<Page model=u'page' id=u'bar'>, <Page model=u'page' id=u'foo'>]</span>
</pre></div>
<div class="child-pages nocontent">
<div class="row">
<div class="col-md-6 child">
<h4>
<i class="glyphicon glyphicon-flash"></i>
<a href="ne/">!=</a>
</h4>
<p class="summary">Compares an expression to another by ensuring inequality.</p>
</div>
<div class="col-md-6 child">
<h4>
<i class="glyphicon glyphicon-flash"></i>
<a href="lt/"><</a>
</h4>
<p class="summary">True if the left side is smaller than the right side.</p>
</div>
</div>
<div class="row">
<div class="col-md-6 child">
<h4>
<i class="glyphicon glyphicon-flash"></i>
<a href="le/"><=</a>
</h4>
<p class="summary">True if the left side is smaller or equal to the right side.</p>
</div>
<div class="col-md-6 child">
<h4>
<i class="glyphicon glyphicon-flash"></i>
<a href="eq/">==</a>
</h4>
<p class="summary">Compares an expression to another.</p>
</div>
</div>
<div class="row">
<div class="col-md-6 child">
<h4>
<i class="glyphicon glyphicon-flash"></i>
<a href="gt/">></a>
</h4>
<p class="summary">True if the left side is larger than the right side.</p>
</div>
<div class="col-md-6 child">
<h4>
<i class="glyphicon glyphicon-flash"></i>
<a href="ge/">>=</a>
</h4>
<p class="summary">True if the left side is larger or equal to the right side.</p>
</div>
</div>
<div class="row">
<div class="col-md-6 child">
<h4>
<i class="glyphicon glyphicon-cog"></i>
<a href="and/">and()</a>
</h4>
<p class="summary">True if both left and right side are true.</p>
</div>
<div class="col-md-6 child">
<h4>
<i class="glyphicon glyphicon-cog"></i>
<a href="contains/">contains()</a>
</h4>
<p class="summary">Checks if an item contains another one.</p>
</div>
</div>
<div class="row">
<div class="col-md-6 child">
<h4>
<i class="glyphicon glyphicon-cog"></i>
<a href="endswith/">endswith()</a>
</h4>
<p class="summary">True if a string ends with another string (case insensitive).</p>
</div>
<div class="col-md-6 child">
<h4>
<i class="glyphicon glyphicon-cog"></i>
<a href="endswith-cs/">endswith_cs()</a>
</h4>
<p class="summary">True if a string ends with another string (case sensitive).</p>
</div>
</div>
<div class="row">
<div class="col-md-6 child">
<h4>
<i class="glyphicon glyphicon-cog"></i>
<a href="or/">or()</a>
</h4>
<p class="summary">True if either left and right side are true.</p>
</div>
<div class="col-md-6 child">
<h4>
<i class="glyphicon glyphicon-cog"></i>
<a href="startswith/">startswith()</a>
</h4>
<p class="summary">True if a string starts with another string (case insensitive).</p>
</div>
</div>
<div class="row">
<div class="col-md-6 child">
<h4>
<i class="glyphicon glyphicon-cog"></i>
<a href="startswith-cs/">startswith_cs()</a>
</h4>
<p class="summary">True if a string starts with another string (case sensitive).</p>
</div>
</div>
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