select PRINCIPAL_NAME,PRINCIPAL_TYPE,substr(string_agg(db_name||'.'||tbl_name,','),1,100)m from (select s.*,(select tbl_name from tbls where tbl_id=s.tbl_id) tbl_name,(select name from dbs where db_id=(select db_id from tbls where tbl_id=s.tbl_id)) db_name from (select principal_name,principal_type,tbl_id from tbl_privs group by principal_name,principal_type,tbl_id) s)tt group by PRINCIPAL_NAME,PRINCIPAL_TYPE ；

试试这个