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Django: show me the SQL

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Here are 6 different ways of inspecting the SQL generated by the ORM of Django.

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  1. Using the query attribute
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  2. Using connection.queries
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  3. In the logs
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  4. Using Django Debug Toolbar
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  5. Using django-extensions and shell_plus
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  6. Using django-extensions and runserver_plus
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Using the query attribute

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  1. Add .query to your queryset. For example:
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qs = User.objects.filter(username="gustave")
+print(qs.query)
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Note: this does not work for the expressions that do not return a QuerySet. For example, those ending with .count() or .exists().

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Using connection.queries

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  1. In your Django settings make sure DEBUG is set to True
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  2. In your code do:
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from django.db import connection, reset_queries
+# reset_queries() # Optional, will empty the query list
+print(connection.queries)
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Official documentation: here

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In the logs

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  1. Add a django.db.backends logger at the level DEBUG in settings.py.
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LOGGING = {
+    'version': 1,
+    'disable_existing_loggers': False,
+    'handlers': {
+        'console': {
+            'class': 'logging.StreamHandler',
+        },
+    },
+    'loggers': {
+        'django.db.backends': {
+            'handlers': ['console'],
+            'level': 'DEBUG',
+        },
+    },
+}
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Tip: add debug log in your code to find where SQL is coming from. The logs

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Using Django Debug Toolbar

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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.

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  1. Install it following the instructions here
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  2. Open the page you want to inspect in your browser and check out the "SQL" section.
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TODO add pic

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Using django-extensions and shell_plus

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  1. python -m pip install django-extensions
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  2. ./manage.py shell_plus --print-sql
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  3. In the shell do a query, for example User.objects.count()
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Official documentation: here

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Using django-extensions and runserver_plus

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  1. python -m pip install django-extensions Werkzeug
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  2. ./manage.py runserver_plus --print-sql
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  3. Do some HTTP requests and look in the logs for the SQL generated
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  4. Killer feature: you can also pass the argument --print-sql-location and a stacktrace will be added to each SQL query to help you find from where it is coming.
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Those parameters are not officially documented, but do exist in the code.

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