Feb-05-2019, 08:03 AM
I am trying to create a simple inventory app using Django. My project came to a stand still when I couldn't find a solution for calculating opening and closing balances on the fly/dynamically. I tried for days researching on the web but no progress yet. If anyone could help i will appreciate.
All I need is a query to calculate opening and closing balances dynamically.
My Models:
I am using item.quantity to store opening stock for the first time only.
Take into consideration that there will be different items and also back dated entries.
help me guys.
All I need is a query to calculate opening and closing balances dynamically.
My Models:
class Item(models.Model): name = models.CharField(max_length=30) buying_price = models.PositiveIntegerField() selling_price = models.PositiveIntegerField() quantity = models.PositiveIntegerField() def __str__(self): return self.name
class SalesSheet(models.Model): txn_date = models.DateField() item = models.ForeignKey(Item, on_delete=models.CASCADE) purchases = models.PositiveIntegerField() sales = models.PositiveIntegerField()What I want after posting purchases and sales is an output like this
Output:id date item opening purchases sales closing
1 1-1-19 abc 10 20 5 25
2 2-12-19 def 25 20 10 35
3 3-1-19 abc 25 10 25 10
4 4-1-19 def 35 10 30 15
5 7-1-19 abc 10 0 0 10
6 9-1-19 def 15 0 5 10
and so on.....I am using item.quantity to store opening stock for the first time only.
Take into consideration that there will be different items and also back dated entries.
help me guys.