Fix: Django ORM, How to join a dropped table, with multiple conditions

 In Django's Object-Relational Mapping (ORM), if you need to "join" a dropped table (a table that no longer exists in the database) and apply multiple conditions, you won't be able to use the standard ORM query methods, as they are designed to work with existing database tables. Instead, you may have to use raw SQL queries to achieve this.


Here's a general outline of how you can use raw SQL to join a dropped table with multiple conditions in Django:


```python

from django.db import connection


def custom_query():

    with connection.cursor() as cursor:

        # Write your SQL query with the JOIN and conditions

        sql_query = """

            SELECT

                a.column1,

                b.column2

            FROM

                your_existing_table AS a

            JOIN

                your_dropped_table AS b

            ON

                a.id = b.foreign_key_id

            WHERE

                a.some_condition = 'value1'

            AND

                b.some_other_condition = 'value2'

        """


        # Execute the SQL query

        cursor.execute(sql_query)


        # Fetch the results

        results = cursor.fetchall()


    return results

```


In this example:


1. You use the `connection.cursor()` context manager to create a database cursor for executing the raw SQL query.


2. In the `sql_query` variable, you write your SQL query. It includes the JOIN between your existing table and the dropped table and specifies the conditions you want to apply.


3. You execute the SQL query using `cursor.execute()`.


4. You fetch the results using `cursor.fetchall()`.


Remember to replace `your_existing_table`, `your_dropped_table`, and the column names in the SQL query with your actual table names and conditions. Also, be cautious when using raw SQL queries, as they can potentially expose your application to SQL injection vulnerabilities. Make sure to properly sanitize and validate any user input used in the query.

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