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<dt>Wed 28 February 2024</dt>
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<dt>Wed 24 January 2024</dt>
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<h1 itemprop="name">Django: show me the SQL</h1>

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<span class="meta__date" itemprop="datePublished" content="2024-02-28">
<span class="glyphicon glyphicon-calendar"></span> &nbsp; Wed 28 February 2024
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<p>Here are 6 different ways of inspecting the SQL generated by the ORM of Django.</p>
<ol>
<li><a href="#anchor-using-query-attribute">Using the <code>query</code> attribute</a></li>
<li><a href="#anchor-using-connection-queries">Using <code>connection.queries</code></a></li>
<li><a href="#anchor-in-the-logs">In the logs</a></li>
<li><a href="#anchor-using-django-debug-toolbar">Using Django Debug Toolbar</a></li>
<li><a href="#anchor-django-extensions-shell-plus">Using django-extensions and shell_plus</a></li>
<li><a href="#anchor-django-extentions-runserver-plus">Using django-extensions and runserver_plus</a></li>
</ol>
<h1>Using the <code>query</code> attribute<a id="anchor-using-query-attribute"></a></h1>
<ol>
<li>Add <code>.query</code> to your queryset. For example:</li>
</ol>
<div class="highlight"><pre><span></span><code><span class="n">qs</span> <span class="o">=</span> <span class="n">User</span><span class="o">.</span><span class="n">objects</span><span class="o">.</span><span class="n">filter</span><span class="p">(</span><span class="n">username</span><span class="o">=</span><span class="s2">&quot;gustave&quot;</span><span class="p">)</span>
<span class="nb">print</span><span class="p">(</span><span class="n">qs</span><span class="o">.</span><span class="n">query</span><span class="p">)</span>
</code></pre></div>

<p><strong>Note:</strong> this does not work for the expressions that do not return a QuerySet. For example, those ending with <code>.count()</code> or <code>.exists()</code>.</p>
<h1>Using <code>connection.queries</code><a id="anchor-using-connection-queries"></a></h1>
<ol>
<li>In your Django settings make sure <code>DEBUG</code> is set to <code>True</code></li>
<li>In your code do:</li>
</ol>
<div class="highlight"><pre><span></span><code><span class="kn">from</span> <span class="nn">django.db</span> <span class="kn">import</span> <span class="n">connection</span><span class="p">,</span> <span class="n">reset_queries</span>
<span class="c1"># reset_queries() # Optional, will empty the query list</span>
<span class="nb">print</span><span class="p">(</span><span class="n">connection</span><span class="o">.</span><span class="n">queries</span><span class="p">)</span>
</code></pre></div>

<p>Official documentation: <a href="https://docs.djangoproject.com/en/5.0/faq/models/#how-can-i-see-the-raw-sql-queries-django-is-running">here</a></p>
<h1>In the logs<a id="anchor-in-the-logs"></a></h1>
<ol>
<li>Add a <code>django.db.backends</code> logger at the level <code>DEBUG</code> in <code>settings.py</code>.</li>
</ol>
<div class="highlight"><pre><span></span><code><span class="n">LOGGING</span> <span class="o">=</span> <span class="p">{</span>
<span class="s1">&#39;version&#39;</span><span class="p">:</span> <span class="mi">1</span><span class="p">,</span>
<span class="s1">&#39;disable_existing_loggers&#39;</span><span class="p">:</span> <span class="kc">False</span><span class="p">,</span>
<span class="s1">&#39;handlers&#39;</span><span class="p">:</span> <span class="p">{</span>
<span class="s1">&#39;console&#39;</span><span class="p">:</span> <span class="p">{</span>
<span class="s1">&#39;class&#39;</span><span class="p">:</span> <span class="s1">&#39;logging.StreamHandler&#39;</span><span class="p">,</span>
<span class="p">},</span>
<span class="p">},</span>
<span class="s1">&#39;loggers&#39;</span><span class="p">:</span> <span class="p">{</span>
<span class="s1">&#39;django.db.backends&#39;</span><span class="p">:</span> <span class="p">{</span>
<span class="s1">&#39;handlers&#39;</span><span class="p">:</span> <span class="p">[</span><span class="s1">&#39;console&#39;</span><span class="p">],</span>
<span class="s1">&#39;level&#39;</span><span class="p">:</span> <span class="s1">&#39;DEBUG&#39;</span><span class="p">,</span>
<span class="p">},</span>
<span class="p">},</span>
<span class="p">}</span>
</code></pre></div>

<p>Tip: add debug log in your code to find where SQL is coming from. The logs</p>
<h1>Using Django Debug Toolbar<a id="anchor-using-django-debug-toolbar"></a></h1>
<p>The initial effort to install the toolbar is a bit higher than the other method. But when working on a website, this is a must have.</p>
<ol>
<li>Install it following the instructions <a href="https://django-debug-toolbar.readthedocs.io/en/latest/installation.html">here</a></li>
<li>Open the page you want to inspect in your browser and check out the "SQL" section.</li>
</ol>
<p>TODO add pic</p>
<h1>Using django-extensions and shell_plus<a id="anchor-django-extensions-shell-plus"></a></h1>
<ol>
<li><code>python -m pip install django-extensions</code></li>
<li><code>./manage.py shell_plus --print-sql</code></li>
<li>In the shell do a query, for example <code>User.objects.count()</code></li>
</ol>
<p>Official documentation: <a href="https://django-extensions.readthedocs.io/en/latest/shell_plus.html#sql-queries">here</a></p>
<h1>Using django-extensions and runserver_plus<a id="anchor-django-extentions-runserver-plus"></a></h1>
<ol>
<li><code>python -m pip install django-extensions Werkzeug</code></li>
<li><code>./manage.py runserver_plus --print-sql</code></li>
<li>Do some HTTP requests and look in the logs for the SQL generated</li>
<li>Killer feature: you can also pass the argument <code>--print-sql-location</code> and a stacktrace will be added to each SQL query to help you find from where it is coming.</li>
</ol>
<p>Those parameters are not officially documented, but do exist in the <a href="https://github.com/django-extensions/django-extensions/blob/81e79826fdbc127060539bcde0325d81c63e59c1/django_extensions/management/commands/runserver_plus.py#L193-L198">code</a>.</p>
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