Multiple database support in django

Question

From some forum I came to know that Multiple database support is added in Django at lower level, but the higher level apis are not added yet.

Can anyone please tell

Answer 1

If you read a few of the many (many) threads on this subject in django-dev, you will see that what looks straightforward, isn't. If you pick a single use case, then it looks easy, but as soon as you start to generalize in any way you start to run into trouble.

To use the above-referenced thread as an example, when you say "multiple databases", which of the following are you talking about?

• All DB on the same machine under the same engine.
• All DB on same machine, different engines (E.g. MySQL + PostgreSQL)
• One Master DB with N read-only slaves on different machines.
• Sharding of tables across multiple DB servers.

Will you need:

• Foreign keys across DBs
• JOINs across machines and/or engines
• etc. etc.

One of the problems with a slick ORM like Django's is that it hides all of those messy details under a nice paint job. To continue to do that, but to then add in any of the above, is Not Easy (tm).