Re: Simple DELETE on modest-size table runs 100% CPU forever

I'm completely baffled by this problem: I'm doing a delete that joins three modest-sized tables, and it gets completely stuck: 100% CPU use forever.  Here's the query:

Aggregate  (cost=193.54..193.55 rows=1 width=8)
  ->  Nested Loop Semi Join  (cost=0.84..193.54 rows=1 width=0)
        Join Filter: (categories.id = c.id)
        ->  Index Scan using i_categories_category_id on categories  (cost=0.42..2.44 rows=1 width=4)
              Index Cond: (category_id = 23)
        ->  Nested Loop Anti Join  (cost=0.42..191.09 rows=1 width=4)
              Join Filter: (c.id = st.id)
              ->  Index Scan using i_categories_category_id on categories c  (cost=0.42..2.44 rows=1 width=4)
                    Index Cond: (category_id = 23)
              ->  Seq Scan on category_staging_23 st  (cost=0.00..99.40 rows=7140 width=4)