How to Efficiently Execute Raw SQL Queries in Django Views?

Refining SQL Queries in Django Views

In certain scenarios, performing raw SQL queries within Django views becomes necessary. This post delves into how to execute such queries effectively.

Executing Raw SQL Queries

To execute a raw SQL query in a Django view, use the connection module and its cursor() method to establish a connection and cursor. With the cursor, queries can be executed using the execute() method.

from django.db import connection

cursor = connection.cursor()
cursor.execute('SELECT count(*) FROM people_person')

Filtering with a WHERE Clause

To apply a filter to your query, add a WHERE clause specifying the filter condition.

cursor.execute('''SELECT count(*) FROM people_person WHERE vote = "yes"''')

Accessing Query Results

Query results can be retrieved using the fetchone() method on the cursor. This returns a tuple containing the result values. For instance, in the example above, the result is the count of all Person objects with vote set to "yes".

row = cursor.fetchone()
print(row)  # Output: (12,)

Implementing in Django Views

To integrate the raw SQL query into a Django view, the code in the question can be modified as follows:

from django.db import connection
from app.models import Picture

def results(request):
    cursor = connection.cursor()
    cursor.execute('''SELECT count(*) FROM app_picture''')
    all_count = cursor.fetchone()[0]

    cursor.execute('''SELECT count(*) FROM app_picture WHERE vote = "yes"''')
    yes_count = cursor.fetchone()[0]

    return render_to_response(
        'results.html', 
        {'all': all_count, 'yes': yes_count}, 
        context_instance=RequestContext(request)
    )

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