Search by foreign key id in admin

Question

I'm trying to achieve something apparently simple but I couldn't find any answer, neither on Google nor here. I have a Django model, something dead-simple:

class Shipment(models.Model):
    id = models.AutoField(primary_key=True)
    transaction = models.ForeignKey(Transaction)

I would like to be able to search in my Shipment Admin page by transaction.id. To clarity, I want this (this code obviously doesn't work):

class ShipmentAdmin(admin.ModelAdmin):
    list_display = ('id', 'transaction')
    search_fields = ['id', 'transaction.id']

This can't work cause transaction.id does not name a field. Any idea? By "search" I mean be able to insert my transaction id inside the search box of the Shipment Admin page, press "search" and automatically retrieve appropriate transactions.

Petropavlovsk

Answer 1

as with the other admin options, you need to use __ for foreign keys e.g.

search_fields = ['id', 'transaction__id']

Syllogize

It doesn't seem to work if you're going up two levels of foreign keys, i.e. 'allocation__project__name' doesn't work where allocation has an FK to project and project has a name. How do you solve that? I keep getting the "<field> is not a callable, an attribute of <model>" – Fichtean

@radtek, that seems to work for me, I can do fk1__fk2__field, only tried in 1.7 tho, are allocation and project just ForeignKey()? – Syllogize

Yeah I know it should work, I even seen an example on django docs but for some reason it isn't working for me. If I don't find a way around it I'll setup a sample repo with the conflicting code. – Fichtean

@Fichtean sorry late reply, strange, probably not, but have you tried removing all the other admin options, just to make sure its not misleading message? – Syllogize

@Syllogize I'll see if I can isolate it and recreate the issue – Fichtean

You'll want to use the equals sign with something like search_fields = ('=id',). Otherwise by default an like query will be done, so a query for 6 could also bring back results for 1556. Not usually the intention. – Reviviscence

Answer 2

search_fields documentation:

You can also perform a related lookup on a ForeignKey or ManyToManyField with the lookup API "follow" notation

Solution:

search_fields = ['id', 'transaction__id']

Orsini

For those getting a Related Field got invalid lookup: icontains error, check that you're actually using the related lookup transaction__id instead of the FK column name transaction_id. – Neukam

Answer 3

By default, the Id field which is the primary key in Django is a BigIntergerField right? That's numbers.

So in one of the model's field transaction table, You should set a primary_key=True.

Then when you reference it, you can enter the name of the foreign key instance.

Eg.

Table Category with one field 'name' is a foreign key in post_category:

I set the field 'name' to be its primary key. So to reference it in searchfields,

I will type:

category__name

Doing this allows me to search by category.

You will need to delete your database and re_migrate unless it'd throw a database error because of the previously stored primary key.

If the answer above doesn't work for you, try this. It totally worked for me.

Ushas

This does not add much on top of the existing answers, and hardly addresses the actual question. – Labroid

Uhmm, I am confused though because I got exactly the same errors. I checked all over the net and couldn't find the solution. – Ushas

I figured the answer by myself and thought it'd be nice to help others. How do you know it doesn't address the question. Faced something similar? – Ushas