SQL Union Все в Джанго Орме - PullRequest
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SQL Union Все в Джанго Орме

1 голос
/ 22 мая 2019

В настоящее время я работаю над проектом, в котором у меня есть нижеописанные таблицы, используя таблицу ниже. Я хочу сделать запрос, который покажет оставшуюся позицию на складе, поэтому я хочу сделать, используя Union All в Django ORM, используя union all в запросе я буду управлять своей позицией на складе, я выполнил запрос SQL, который я также описал ниже, для получения ожидаемого результата. 

class PurchaseHeader(models.Model):
    purchase_no = models.CharField(max_length=100, unique=True)
    date = models.DateField(default=datetime.date.today)
    footer_description = models.TextField()
    payment_method = models.CharField(max_length=100)
    cartage_amount = models.DecimalField(max_digits=8, decimal_places=2)
    additional_tax = models.DecimalField(max_digits=8, decimal_places=2)
    withholding_tax = models.DecimalField(max_digits=8, decimal_places=2)
    account_id = models.ForeignKey(ChartOfAccount, models.SET_NULL, blank=True, null=True)


class PurchaseDetail(models.Model):
    item_code = models.CharField(max_length=100)
    item_name = models.CharField(max_length=100)
    item_description = models.TextField()
    unit = models.CharField(max_length=100)
    quantity = models.IntegerField()
    cost_price = models.DecimalField(max_digits=8, decimal_places=2)
    retail_price = models.DecimalField(max_digits=8, decimal_places=2)
    sales_tax = models.DecimalField(max_digits=8, decimal_places=2)
    purchase_id = models.ForeignKey(PurchaseHeader, on_delete=models.CASCADE)


class PurchaseReturnHeader(models.Model):
    purchase_no = models.CharField(max_length=100, unique=True)
    date = models.DateField(default=datetime.date.today)
    footer_description = models.TextField()
    payment_method = models.CharField(max_length=100)
    cartage_amount = models.DecimalField(max_digits=8, decimal_places=2)
    additional_tax = models.DecimalField(max_digits=8, decimal_places=2)
    withholding_tax = models.DecimalField(max_digits=8, decimal_places=2)
    account_id = models.ForeignKey(ChartOfAccount, models.SET_NULL, blank=True, null=True)

class PurchaseReturnDetail(models.Model):
    item_code = models.CharField(max_length=100)
    item_name = models.CharField(max_length=100)
    item_description = models.TextField()
    unit = models.CharField(max_length=100)
    quantity = models.IntegerField()
    cost_price = models.DecimalField(max_digits=8, decimal_places=2)
    retail_price = models.DecimalField(max_digits=8, decimal_places=2)
    sales_tax = models.DecimalField(max_digits=8, decimal_places=2)
    purchase_return_id = models.ForeignKey(PurchaseReturnHeader, on_delete=models.CASCADE)


class SaleHeader(models.Model):
    sale_no = models.CharField(max_length=100, unique=True)
    date = models.DateField(default=datetime.date.today)
    footer_description = models.TextField()
    payment_method = models.CharField(max_length=100)
    cartage_amount = models.DecimalField(max_digits=8, decimal_places=2)
    additional_tax = models.DecimalField(max_digits=8, decimal_places=2)
    withholding_tax = models.DecimalField(max_digits=8, decimal_places=2)
    account_id = models.ForeignKey(ChartOfAccount, models.SET_NULL, blank=True, null=True)


class SaleDetail(models.Model):
    item_code = models.CharField(max_length=100)
    item_name = models.CharField(max_length=100)
    item_description = models.TextField()
    unit = models.CharField(max_length=100)
    quantity = models.IntegerField()
    cost_price = models.DecimalField(max_digits=8, decimal_places=2)
    retail_price = models.DecimalField(max_digits=8, decimal_places=2)
    sales_tax = models.DecimalField(max_digits=8, decimal_places=2)
    sale_id = models.ForeignKey(SaleHeader, on_delete=models.CASCADE)


class SaleReturnHeader(models.Model):
    sale_no = models.CharField(max_length=100, unique=True)
    date = models.DateField(default=datetime.date.today)
    footer_description = models.TextField()
    payment_method = models.CharField(max_length=100)
    cartage_amount = models.DecimalField(max_digits=8, decimal_places=2)
    additional_tax = models.DecimalField(max_digits=8, decimal_places=2)
    withholding_tax = models.DecimalField(max_digits=8, decimal_places=2)
    account_id = models.ForeignKey(ChartOfAccount, models.SET_NULL, blank=True, null=True,)


class SaleRetutnDetail(models.Model):
    item_code = models.CharField(max_length=100)
    item_name = models.CharField(max_length=100)
    item_description = models.TextField()
    unit = models.CharField(max_length=100)
    quantity = models.IntegerField()
    cost_price = models.DecimalField(max_digits=8, decimal_places=2)
    retail_price = models.DecimalField(max_digits=8, decimal_places=2)
    sales_tax = models.DecimalField(max_digits=8, decimal_places=2)
    sale_return_id = models.ForeignKey(SaleReturnHeader, on_delete=models.CASCADE)

И я хочу сделать запрос, подобный этому 

SELECT item_code, SUM(quantity) AS qty FROM (
    SELECT 'Purchase' AS TranType,Item_Code,Quantity FROM transaction_purchasedetail
    UNION All
    SELECT 'Purchase Return' AS TranType,Item_Code,Quantity * -1 FROM transaction_purchasereturndetail
    UNION All
    SELECT 'Sale' AS TranType,Item_Code,Quantity * -1 FROM transaction_saledetail
    UNION All
    SELECT 'Sale Return' AS TranType,Item_Code,Quantity  FROM transaction_saleretutndetail
) AS tblTemp GROUP BY Item_Code

Я выполнил вышеуказанный SQL-запрос в браузере БД SQLite и получил ожидаемый результат Как я могу сделать это в Django ORM.

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