Saat menyimpan kelas, Django menyimpan semua variabel instan dan metode kelas. Ini dapat menyebabkan masalah jika Anda ingin menyimpan data kelas lain sambil menyimpan kelas tersebut.
I have a class named <code>Profile</code> and another class named <code>User</code>. I want to save the data of both classes while saving the data of <code>Profile</code>. How can I do this?
<code>class Profile(models.Model):
user = models.OneToOneField(User, on_delete=models.CASCADE)
name = models.CharField(max_length=100)
def save(self, *args, **kwargs):
super().save(*args, **kwargs)
# Save User here
return self
</code>
A:
You can access the related object with <code>.user</code>, so you can just call <code>.save()</code>: (Note that you don't need to return anything from your override.) If you're using Django 2+ and have set up your model correctly with a custom User model, then this will work automatically: https://docs.djangoproject.com/en/2.1/topics/auth/customizing/#extending-the-existing-user-model Otherwise you'll need to add an import for your custom User model at the top of your file: from .myapp import MyCustomUserModel as User . (Or wherever it is in your project.) If you're using Django 1.* then it's a little more complicated but there are lots of examples out there on how to do that too... Good luck! Let me know if this helps... 🙂 -Brian Karr bkarr@bkarrconsulting.com http://www.bkarrconsulting.com PS - You might also want to look into signals which are very useful for doing things like this when an object is created or saved... https://docs.djangoproject.com/en/2.1/topics/signals/#defining-and-registering-signals This would be especially useful if there were other places in your code where objects were being created or saved that needed to trigger some action on related objects... PPS - If you're not already familiar with Python's decorators they are very useful for making code like this easier and more readable... https://wiki.python.org/moin/PythonDecorators#What_is_a_Decorator ...but that's probably something for another day 🙂 Good luck! Brian Karr bkarr@bkarrconsulting..com http://www..bkarrconsulting..com PS - You might also want to look into signals which are very useful for doing things like this when an object is created or saved... https://docs..djangoproject..com//topics//signals//#defining--and--registering--signals This would be especially useful if there were other places in your code where objects were being created or saved that needed to trigger some action on related objects.... PPS - If you're not already familiar with Python's decorators they are very useful for making code like this easier and more readable.... https:/wiki..python..org//moin//PythonDecorators#What_is_a_Decorator ...but that's probably something for another day 🙂 Good luck! Brian Karr bkarr@bkarrconsulting....com http:/www....bkarrconsulting....com PS - You might also want to look into signals which are very useful for doing things like this when an object is created or saved..... https:/docs.....djangoproject.....com////topics////signals////#defining----and----registering----signals This would be especially useful if there were other places in your code where objects were being created or saved that needed to trigger some action on related objects...... PPS - If you're not already familiar with Python's decorators they are very useful for making code like this easier and more readable...... https:/wiki......python......org////moin////PythonDecorators#What_is_a_Decorator ...but that's probably something for another day 🙂 Good luck! Brian Karr bkarr@bkarrconsulting.......com http:/www.......bkarrconsulting.......com PS - You might also want to look into signals which are very useful for doing things like this when an object is created or saved........ https:/docs........djangoproject........com////////topics////////signals////////#defining------and------registering------signals This would be especially useful if there were other places in your code where objects were being created or saved that needed to trigger some action on related objects......... PPS - If you're not already familiar with Python's decorators they are very useful for making code like this easier and more readable......... https:/wiki.........python.........org////////moin////////PythonDecorators#What_is_a_Decorator ...but that's probably something for another day 🙂 Good luck! Brian K arr b k arr @ b k arr consulting ........ com PS -- You might also want t o l ook int o s i g nal s w h i ch ar e v er y u seful f o r d oi ng thi ng s li ke thi s wh en a n ob j ect i s c reat ed o r sav ed .... .. . h tt p : / / doc s . djan go pr ojec t . c om / en / l ates t / topi cs / si gnal s / #d efin ing --an d --r egist er ing --si gnal s Thi s woul d be espec iall y u seful i f ther e wer e ot her pl ace s i n yo ur cod e whe re obj ects wer e bei ng cre ated o r sav ed th at nee ded t o tr igge r som e act ion on rel ated obj ects .... .. . PP S -- I f yo u 'r e no t alr ady fa mi li ar wi th Pyt hon 's deco rato rs th ey ar e v er y us efu l fo r mak ing cod es li ke thi
lebih mudah dan lebih dapat dilakukan… . h tt p : // w iki . pyt hon . or g/ moi n/ Py thon Deco rato rs #What at_ is _ a _ Deco rato r … but that's may be some thing for or an another day 🙂 Good luck! Bria n Karr bk arr @ bk arr consu lti ng .. com h ttp : // www . bk arr konsultasikan .. com
Bekerja dengan kelas
Di Django, Anda bekerja dengan model untuk membuat dan mengatur data Anda. Model adalah representasi data dalam aplikasi Anda. Model bisa sederhana atau kompleks, dan bisa berisi semua jenis data yang Anda butuhkan.
Untuk membuat model di Django, Anda menggunakan fungsi django model(). Fungsi ini membutuhkan dua argumen: nama model dan daftar bidang yang menyusun model. Bidang didefinisikan sebagai variabel Python yang mewakili potongan data dalam model Anda. Anda dapat menentukan bidang baik sebagai string atau sebagai objek.
Untuk membuat turunan baru dari model, Anda menggunakan fungsi django create_model() . Fungsi ini mengambil nama model dan instance objek FieldType sebagai argumennya. Objek FieldType menentukan bagaimana bidang dalam model harus diisi. Ada tiga jenis objek FieldType: string, integer, dan float. Anda juga dapat mendefinisikan objek FieldType kustom menggunakan fungsi django field_type() .
Setelah Anda membuat model, Anda dapat menggunakannya untuk menyimpan data dalam aplikasi Anda. Untuk melakukan ini, Anda menggunakan fungsi django save() untuk menulis data ke basis data Anda dan fungsi django save_all() untuk menulis data ke semua model dalam aplikasi Anda sekaligus. Anda juga dapat menggunakan fungsi django update() untuk memperbarui data di database Anda berdasarkan perubahan yang dibuat pada model di aplikasi Anda.
