listagg Oracle SQL查询，在同一表上联接

Question

For every dog, I'd like to find the matching names of other animals besides dog, and add them in a comma-separated list. Images of table and desired results of query below:

A table exists with this structure:

And I would like to create a query with results such as:

Answer 1

You can use a self-join and then a listagg .

select tdog.animal,tdog.name
,listagg(tother.animal||'-'||tother.name||'-'||tother.id) within group(order by tother.id)
from tablename tdog
join tablename tother on tdog.name=tother.name and tdog.animal='dog' and tother.animal <> 'dog'
group by tdog.animal,tdog.name

Answer 2

With some tricks, you don't need a self join :

select 'dog' as animal, name,
       listagg(case when animal <> 'dog' then animal || '-' || name || '-' || id
               end), ',') within group (order by id) as animals
from t
group by name
having sum(case when animal = 'dog' then 1 else 0 end) > 0