Python用一对多关系填充数据库

Question

I'm a beginner, so please go easy on me. I am working on a script so that I don't have to keep entering in data when I decide to drop the database. My entire script works well, except when I'm dealing with a one-to-many relationship. It will not save to the database. Can anyone tell me what I am doing wrong or point me in the right direction?

SCRIPT:

try:
 pmod.Instrument.objects.get(title='kjkjsdfsadfs')
except pmod.Instrument.DoesNotExist:
 u = pmod.Instrument()
 u.title = 'Bach 42 Trombone'
 u.price = 550.00
 u.soundDescription = 'Good'
 u.functionalityDescription = 'Good'
 u.damageDescription = 'Good'
 u.accessoryDescription = 'Good'
 u.customerName = 'Jake'
 u.customerEmail = 'ks@gmail.com'
 u.instrumentCategory = 1
 print('Good2')
 u.save()

 print('Instrument1 saved')

MODEL:

class Category(models.Model):
    instrumentCategory=models.CharField(max_length=50,blank=True,null=True)
    def __str__(self):
        return self.instrumentCategory

class Instrument(models.Model):
    title = models.CharField(help_text='title',max_length=50,blank=True,null=True)
    price = models.DecimalField(max_digits=8, decimal_places=2)
    soundDescription=models.CharField(max_length=1000,blank=True,null=True)
    functionalityDescription=models.CharField(max_length=1000,blank=True,null=True)
    damageDescription=models.CharField(max_length=1000,blank=True,null=True)
    accessoryDescription=models.CharField(max_length=1000,blank=True,null=True)
    customerName=models.CharField(max_length=50,blank=True,null=True)
    customerEmail=models.EmailField(max_length=254,help_text='Enter valid email address')
    instrumentCategory=models.ForeignKey(Category)

Answer 1

u.instrumentCategory = 1

That's not how a models.ForeignKey field works in Django. You need to get an instance of the Category object and assign that to u.instrumentCategory .

u.instrumentCategory = pmod.Category.objects.get(id=1)

Answer 2

You may try :

u.instrumentCategory_id = 1