I have weird problem after migrating Magento Community 188.8.131.52 to production server. My store has only configurable products and all simple products are set as Not visible individually. While ordering everything works fine, but after order is finished and you go to Order history or in Admin Orders you can see some simple products shown separately. They have price 0$ since they are only options of Configurable products and not meant to be shown anywhere. On my development server this never happens.
I also looked in database in table sales_flat_order_item and noticed that these particular products have parent_item_id set to null, and not as their parent configurable item. And this happens only sometimes in some orders, randomly.
Also I have noticed that all these problematic simple products have increment id in sales_flat_order_item smaller than their parent configurable item, as they are inserted to database before parent. In dev server this never happens. It is also not logical, since configurable product should always be created first in order to get increment id which is later used for its child.
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