thinkPHP查询求大神帮忙

select d.*,(select count(*) from cmf_course_major where did=d.id) as major_count,(select count(*) from cmf_course_category where did=d.id) as category_count from cmf_course_department这样的查询语句怎么改成Thinkphp那种封装的查询

在Model的link里面，添加‘mapping_fields’_，可以使用count()函数'mapping_fields' => 'count(*) '
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