Django foreign-key cannot assign must be a instance

[ratnadeep ray]

Hi all, 

I am trying to add a row in the DB using the following views.py: 

# Create your views here.
from django.shortcuts import render
from fusioncharts.models import Component,Report
import xlrd
def pie_chart(request):
    labels = []
    data = []
    loc = ("C:\Django_apps\QRC_Report.xlsx")
    workbook = xlrd.open_workbook(loc) 
    worksheet = workbook.sheet_by_name('Sheet1')
    num_rows = worksheet.nrows - 1
    num_cols = worksheet.ncols - 1
    curr_row = -1
    component = []
    comp = None 
    while curr_row < num_rows:
      curr_row += 1
      row = worksheet.row(curr_row)
      curr_col = -1
      if "Header" in worksheet.cell_value(curr_row, 0):
        compon = worksheet.cell_value(curr_row, 0).strip("*")
        print("The component is %s" %compon)
        component.append(compon)
        print("===========The results of the component %s is as follows============" %compon)
        Component.objects.create(comp=compon)
        continue
      while curr_col < num_cols:
        curr_col += 1
        cell_value = worksheet.cell_value(curr_row, curr_col)    
        #print("Cell value = %s" %cell_value)
        test_name = worksheet.cell_value(curr_row,0)
        print("Test name = %s" %test_name)
        test_value = worksheet.cell_value(curr_row,1)
        print("Test result = %s" %test_value)
        print("The component is = %s" %comp)
        Report.objects.create(param=test_name,comp=compon,value=test_value)
    return render(request, 'pie_chart.html', {
        'labels': labels,
        'data': data,
    })

However the above highlighted line is throwing the following error: 

Cannot assign "'Header SQL Detailed'": "Report.comp" must be a "Component" instance.

My model is as follows: 

from django.db import models
from django.urls import reverse
from decimal import Decimal
# Create your models here.
class Component(models.Model):
    comp = models.CharField(max_length=30)
class Report(models.Model):
    comp = models.ForeignKey(Component,on_delete=models.CASCADE)
    param = models.CharField(max_length=30)
    value = models.DecimalField(max_digits=25,decimal_places=18,default=Decimal('0.0000'))

Can anyone please point out what is going wrong here? What should be the correction? 

Thanks. 

[Aldian Fazrihady]

Use comp_id= instead of comp=

Regards,

Aldian Fazrihady
http://aldianfazrihady.com

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[ratnadeep ray]

Can you please say in which line we should make that change because in so many places I am using comp. So in all the places should I change that ?

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[Aldian Fazrihady]

replace
```
Report.objects.create(param=test_name,comp=compon,value=test_value)
```
with
```
Report.objects.create(param=test_name,comp_id=compon,value=test_value)
```

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--

[saqlain abbas]

try to pass -1.0 

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