CODEWITHSUNDEEP
pythondjango
GreenSaber
GreenSaber

Reputation: 1148

Appending to an object in Django

I need to append information to an object in Django rather than update it. I have this database:

Database:
-----------------------
ColA  |  ColB
-----------------------
1     |  "Test string."

And the code that updates:

o = Model.objects.select_related().filter(ColA=1).update(
    ColB = "Entry 2")

This will set ColB to Entry 2. I want to be able to append rather than update. Is there a way I can append the text so that ColB will be set to "Test string. Entry 2."?

Upvotes: 1

Views: 3705

Answers (2)

Daniel Roseman
Daniel Roseman

Reputation: 599610

You can, but it's a bit fiddly.

from django.db.models import Value
from django.db.models.functions import Concat

Model.objects.select_related().filter(ColA=1).update(ColB=Concat('ColB', Value('Entry 2')))

It's probably easier to just get the item, modify it, and save it:

o = Model.objects.get(ColA=1)
o.ColB += "Entry 2"
o.save()

Upvotes: 5

Satevg
Satevg

Reputation: 1601

objects = Model.objects.select_related().filter(ColA=1)
for o in objects:
    o.colB = o.colB + ' Entry 2.'
    o.save()

Upvotes: 0

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