How to know when a record is added to or removed from a many to many relationship?

[Stodge]

I have a model with a many to many relationship. I need to know when a record is added to or removed from the many to many.

Is this possible? Thanks

[yingi keme]

I dont particularly understand how you wish to be updated and know when a record is added or removed. 

Nevertheless, you can make use of django signals (Thanks to melvyn). It will be of great help.

Yingi Kem

On 13 Jun 2017, at 12:54 PM, Stodge <sto...@gmail.com> wrote:

I have a model with a many to many relationship. I need to know when a record is added to or removed from the many to many.

Is this possible? Thanks

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[Stodge]

Thanks. Yes I can use the m2m_changed signal but I need to know specifically if a record was added or if it was removed, not just that the m2m changed.

[Larry Martell]

Perhaps you can use a database trigger.

[Mike Stoddart]

Ah of course, why didn't I think of that! Thanks.

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[Melvyn Sopacua]

On Tuesday 13 June 2017 05:32:35 Stodge wrote:

> Thanks. Yes I can use the m2m_changed signal but I need to know

> specifically if a record was added or if it was removed, not just that

> the m2m changed.

 

So you haven't actually checked the callback signature then (psst, the 'action' keyword argument).

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Melvyn Sopacua