select owner, sum(num_dogs), sum(num_cats) from (select owner, 1 as num_dogs, 0 as num_cats from dogs union select owner, 0 as num_dogs, 1 as num_cats from cats)group by owner
select owner, sum(num_dogs), sum(num_cats) from (select owner, 1 as num_dogs, 0 as num_cats from dogs union select owner, 0 as num_dogs, 1 as num_cats from cats)group by owner
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