I poked around but didn't see this addressed elsewhere - why is url_alias still indexed by a text string ('node/NID')? Every query to this table needs to concatenate a string value prior to the join, so joins are incredibly inefficient. I can understand needing a special case for non-node storage, but when making editorial tools, Views Bulk Operations, or even just large output sets, screen load / query times are just horrible when paths are included in the output.
It would be much better if url_alias had the same entity_type/entity_id/bundle fields that other tables did, or better still, used Entity API for its data storage. I'd even be willing to do this myself - but I wanted to check in with the community on acceptance / desire before starting it.
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