# Active record interface query

**URL:** <https://www.ruby-forum.com/t/active-record-interface-query/189364>\
**Category:** Rails\
**Created:** [May 29, 2010, 8:25pm UTC](https://www.ruby-forum.com/t/active-record-interface-query/189364 "2010-05-29T20:25:16Z")\
**Posts on this page:** 1\
**Page:** 1

<div class="post-metadata">

**Author:** ![girlcarina](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/g/0ea827/32.png) [@girlcarina](https://www.ruby-forum.com/u/girlcarina)\
**Post date:** [May 29, 2010, 8:25pm UTC](https://www.ruby-forum.com/t/active-record-interface-query/189364/1 "2010-05-29T20:25:16Z")

</div>

Olá, tudo bem… sou nova em ROR e estou precisando de ajuda com o  
active query…  
Bom… tenho 3 models…  
Staff, Appointment e Service…  
Gostaria de saber quanto que esse staff gerou de serviço…  
Obs… O Staff possui 2 models filhos (Employees e Freelancer)  
GOstaria de saber com faço isso… fiz um sql, mas não sei como coloco  
isso no código  
SELECT count(S.value)  
FROM Staff SF INNER JOIN Appointment A ON (SF.id = A.staff\_id)  
INNER JOIN Service S ON (A.service\_id = S.id)

Alguém pode me ajudar??