Django bulk_create() with update_conflicts Limitations

Based on the Django 5.1 documentation, the bulk_create() method does have specific limitations regarding conflict handling that vary by database backend.

Current Support for update_conflicts

According to the documentation, the update_conflicts parameter is supported on all databases except Oracle. However, there are additional requirements for PostgreSQL and SQLite:

On databases that support it (all except Oracle), setting the
`update_conflicts` parameter to `True`, tells the database to update
`update_fields` when a row insertion fails on conflicts. On PostgreSQL and
SQLite, in addition to `update_fields`, a list of `unique_fields` that may
be in conflict must be provided.

MySQL/MariaDB Specific Behavior

The documentation specifically mentions a warning about MySQL and MariaDB behavior with the ignore_conflicts parameter, but doesn't explicitly mention any issues with update_conflicts on these databases:

Warning

On MySQL and MariaDB, setting the `ignore_conflicts` parameter to
`True` turns certain types of errors, other than duplicate key, into
warnings. Even with Strict Mode. For example: invalid values or
non-nullable violations.

Possible Explanation

The StackOverflow post you referenced suggests there might be a bug or limitation with MySQL's implementation of update_conflicts in Django. This could be because:

1. MySQL might handle upsert operations differently than PostgreSQL or SQLite
2. Django's implementation might not fully support all MySQL's upsert capabilities

Recommendation

If you're experiencing issues with update_conflicts on MySQL, you might want to consider these alternatives:

1. Use a raw SQL query with MySQL's ON DUPLICATE KEY UPDATE syntax
2. Implement a custom solution using Django's transaction management
3. Use get_or_create() in a loop (less efficient but more reliable)

For example, a raw SQL approach might look like:

PYTHONCopied
from django.db import connection

# Assuming your model has uuid and update_time fields
with connection.cursor() as cursor:
    cursor.execute("""
        INSERT INTO your_table (uuid, other_fields, update_time) 
        VALUES (%s, %s, %s)
        ON DUPLICATE KEY UPDATE update_time = VALUES(update_time)
    """, [uuid_value, other_value, update_time])

If this is a critical issue for your application, you might want to check Django's issue tracker or consider filing a bug report with a minimal reproducible example.