需求：按照项目名，以逗号合并参与人

presto

select 
    item_name
    ,array_join(array_agg(name),',') as group_name
from 
    test.test_04
group by 
    item_name
order by item_name 

hive

select 
    item_name
    ,concat_ws(',',collect_set(name)) as group_name
from 
    test.test_04
group by 
    item_name
order by item_name 

mysql

select 
    item_name,
    group_concat(name,',') as group_name 
from 
    test_prc
group by item_name