CODEWITHSUNDEEP
pythondjango
shashisp
shashisp

Reputation: 2969

How to save list of objects in django models?

I have a list of objects generated after some function, i want it to be saved in django model i tried query set operation

mylist = [(u'england', u'1', u'cde', u'IMG1', u'CP1'), (u'england', u'1', u'cde', u'IMG2', u'CP1'), (u'england', u'2', u'abc', u'IMG1', u'CP1')] 

class Mymodel(models.Model):
   batch_id = models.AutoField(primary_key=True)
   batch_cola = models.CharField(max_length=100)
   batch_colb = models.CharField(max_length=100)
   batch_colc = models.CharField(max_length=100)
   batch_cold = models.CharField(max_length=100)
   batch_cole = models.CharField(max_length=100)

Upvotes: 10

Views: 28331

Answers (3)

kreld
kreld

Reputation: 752

You can use the bulk_create method - something like:

Mymodel.objects.bulk_create([Mymodel(**{'batch_cola' : m[0],
                                        'batch_colb' : m[1],
                                        'batch_colc' : m[2],
                                        'batch_cold' : m[3],
                                        'batch_cole' : m[4]})
                            for m in mylist])

Instead of iterating over the objects and calling save() on every single one of them, this method results in a single database hit for all the objects, as opposed to one hit for each object.

Upvotes: 20

dannymilsom
dannymilsom

Reputation: 2406

Creating new instances of a model are well documented - see creating objects

But to explicitly anwser your question - one solution is to loop over the list of tuples, pass the appropriate keyword arguments to the model class and then call save(). The last bit is important, otherwise there will be no database level transaction.

for t in mylist:
    Mymodel(batch_cola=t[0], batch_colb=t[1],
           batch_colc=t[2], batch_cold=t[3],
           batch_cole=t[4]).save()

You can also use the convenience create() function from the models manager - you don't need to call .save() then.

for t in mylist:
    Mymodel.object.create(batch_cola=t[0], batch_colb=t[1],
           batch_colc=t[2], batch_cold=t[3], batch_cole=t[4])

The docs say that the two are equivalent - so its somewhat a matter of preference.

On a side note, there is a naming convention in Python you should follow when creating Classes - "Class names should normally use the CapWords convention." - see PEP-8 guidelines

class MyModel(models.Model):
    ...

Upvotes: 2

Mikko Ohtamaa
Mikko Ohtamaa

Reputation: 83788

You can use ForeignKey relationship to have a list of objects "contained" by parent object.

Example:

class Parent(models.Model):
    name = models.TextField()

class Child(models.Model):
    name = models.TextField()
    parent = models.ForeignKey(Parent)

Then:

p = Parent.objects.create(name="p")
c = p.child_set.create(name="c")
c2 = p.child_set.create(name="c2")

p.child_set.count()  # Should be 2

For further information refer to ForeignKey documentation in Django.

Upvotes: 0

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