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Editorial Team
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Asked: 2026-06-11T06:46:29+00:00

I have the following model: class Message(Model): url = URLField(URL) email = EmailField(E-Mail) contacted

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I have the following model:

class Message(Model):
    url = URLField("URL")
    email = EmailField("E-Mail")
    contacted = BooleanField("Contacted", default=False)

With example data like:

| url | email           | contacted |
+-----+-----------------+-----------+
| foo | foo@example.com | N         |
| bar | bar@example.com | N         |
| baz | foo@example.com | Y         |

I would like to select all distinct rows (by e-mail address) whose e-mail addresses have never been contacted. With this example data, the bar@example.com row would be the only one returned.

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1 Answer

  1. Editorial Team

    This will return the records you want:

    not_contacted = Message.objects.exclude(
    email__in=Message.objects.filter(contacted=True).values('email')
)

    This has the advantage of only running one query. Your query will look something like this:

    SELECT
    messages_message.id, messages_message.url, messages_message.email, messages_message.contacted
FROM
    Messages
WHERE NOT
    (messages_message.email IN
        ( SELECT U0.email from messages_message U0 WHERE U0.contacted = True )
    )

    Note that for many, many records this query may not be optimal, but it will probably work for most uses.

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