Django database synchronization glitch: Records only appear post manual commit

Backend
1

I’m working on a Django project where several processes communicate with a MySQL backend. One process creates new entries, while another tries to retrieve these entries. The issue is that the reader process doesn’t see the newest entries unless I explicitly trigger a commit using connection._commit().

I’ve tried looking for a smoother approach so that the reader process automatically sees the new entries. For example, in one process, I create a record with a call to MyModel.objects.create(name=‘Record A’); then, in the other process, I attempt to list them using MyModel.objects.all(). Without a manual commit, the new record is absent. Any insights on how to resolve this automatic synchronization would be appreciated.

Here is an altered code example:

# Process for adding records

def add_entry():
    MyModel.objects.create(name='Record A')

# Process for retrieving records

def fetch_entries():
    entries = MyModel.objects.all()
    print(entries)  # Record A is missing initially
    connection._commit()
    entries = MyModel.objects.all()
    print(entries)  # Record A appears after manual commit

Thank you for any suggestions!

2

This issue often stems from Django’s transaction management. By default, Django uses atomic transactions, which means changes aren’t visible to other database connections until committed. To address this, you might want to consider using AUTOCOMMIT mode or explicitly managing transactions.

For AUTOCOMMIT, you can set ATOMIC_REQUESTS = False in your database configuration. This will commit each query immediately, making changes visible to other processes instantly.

Alternatively, you could use Django’s transaction management decorators or context managers to explicitly control when transactions are committed. For example:

from django.db import transaction

@transaction.atomic
def add_entry():
    MyModel.objects.create(name='Record A')

This ensures the transaction is committed right after the creation. Remember, while this solves the visibility issue, it might impact performance if you’re doing many small operations. Always consider the trade-offs for your specific use case.

3

hey, have u checked ur database isolation level? might be set to READ COMMITTED or higher. try adjusting it to READ UNCOMMITTED if possible. this could let ur reader process see changes immediately. just remember it might cause some data inconsistency issues, so use with caution!

4

have u considered using django’s transaction.atomic() decorator? it might help with ur synchronization issue. what about implementing a polling mechanism in the reader process? could check for new entries every few seconds. curious to hear if you’ve explored these options or if there’s a specific reason they wouldn’t work for ur setup?