从postgresql返回不同的数据类型

I have the below query in PG

我在PG中有以下查询

SELECT
project.project_id,
project.project_name,
   category.category_name,
   array_agg(row(skill.skill_name,projects_skills.projects_skills_id)) AS skills
  FROM project
    JOIN projects_skills ON project.project_id = projects_skills.project_id
    JOIN skill ON projects_skills.skill_id = skill.skill_id
    JOIN category ON project.category_id = category.category_id
 GROUP BY project.project_name,project.project_id, category.category_name;
SEL