Composite entity: Table 0 does not exist

You might be familiar with error "Table 0 does not exist" when working with composite data entity import in Dynamics 365 for Finance and Operations. Your entity seems correct, you have a nice file and can't find where the problem is. We had succsfully implemented many composite entity interfaces and they were working smoothly. But after applying Platform Update 9 they suddenly stopped working, giving that strange error message.

It took some while to figure it out, but the reason was a fault in our entities combined with a new feature with "Refresh entity list" functionality in D365fFO.

As you might know, set based processing does not work with composite entities. And, when developing an entity, you can a set a Yes/No property for "Support set based SQL operations". Before PU9, this property simply meant that you were allowed to enable Set based processing for the entity in Data entities form. But with PU9, when you refresh the entity list, it will automatically enable set based processing on every entity that supports it.

If you try to import a composite entity file while set based processing for the related (sub) entities are enabled, you will get error "Table 0 does not exist".

In a way this automatic enabling of set based processing makes sense, but it still feels like a bug. Of course you shouldn't set "Support set based SQL operations" when developing a composite entity. But with the current behavior of the system, every entity will be set for set based processing every time you refresh the entity list. So if you for any reason don't want to have set based processing for an entity that supports it, you will have to disable it manually every time that refresh is executed.

I hope that this feature will be changed back to the way it was. Anyway if you ever run into this error message, you'll know where to look first.