優化一個SQL Server查詢

Question

我有一個SQL Server查詢：

(
    SELECT k12_dms_contacts_institution_jobtitles.job_title_id AS id 
    FROM k12_dms_contacts_institution_jobtitles 
      INNER JOIN k12_dms_institution_master ON k12_dms_institution_master.id = k12_dms_contacts_institution_jobtitles.inst_id 
    WHERE (
       k12_dms_institution_master.state_id='63' 
       AND k12_dms_contacts_institution_jobtitles.glevel_id='1' 
      ) 
    GROUP BY 
      k12_dms_contacts_institution_jobtitles.job_title_id 
) 
INTERSECT 
(
    SELECT k12_dms_contacts_institution_jobtitles.job_title_id AS id 
    FROM k12_dms_contacts_institution_jobtitles 
      INNER JOIN k12_dms_institution_master ON k12_dms_institution_master.id = k12_dms_contacts_institution_jobtitles.inst_id 
    WHERE (
       k12_dms_institution_master.state_id='63' 
       AND k12_dms_contacts_institution_jobtitles.glevel_id='2' 
      ) 
    GROUP BY 
      k12_dms_contacts_institution_jobtitles.job_title_id 
) 
INTERSECT 
(
    SELECT k12_dms_contacts_institution_jobtitles.job_title_id AS id 
    FROM k12_dms_contacts_institution_jobtitles 
      INNER JOIN k12_dms_institution_master ON k12_dms_institution_master.id = k12_dms_contacts_institution_jobtitles.inst_id 
    WHERE (
       k12_dms_institution_master.state_id='63' 
       AND k12_dms_contacts_institution_jobtitles.glevel_id='3' 
      ) 
    GROUP BY 
      k12_dms_contacts_institution_jobtitles.job_title_id 
) 
INTERSECT 
(
    SELECT k12_dms_contacts_institution_jobtitles.job_title_id AS id 
    FROM k12_dms_contacts_institution_jobtitles 
      INNER JOIN k12_dms_institution_master ON k12_dms_institution_master.id = k12_dms_contacts_institution_jobtitles.inst_id 
    WHERE (
       k12_dms_institution_master.state_id='63' 
       AND k12_dms_contacts_institution_jobtitles.glevel_id='4' 
      ) 
    GROUP BY 
      k12_dms_contacts_institution_jobtitles.job_title_id 
) 

有什麼辦法來優化上述query.Intersection只需要在哪裏clause.I想獲取所有的 的基礎上，所有職等都通用的職位。

Answer 1

可以使查詢更加簡潔如下：

SELECT IJT.job_title_id AS id 
FROM k12_dms_contacts_institution_jobtitles AS IJT 
INNER JOIN k12_dms_institution_master AS IM 
ON IM.id = IJT.inst_id 
WHERE IM.state_id='63' 
AND IJT.glevel_id IN ('1', '2', '3', '4') 
GROUP BY IJT.job_title_id 
HAVING COUNT(DISTINCT IJT.glevel_id) = 4 

Answer 2

這是你在找什麼。 （未經測試）

SELECT k12_dms_contacts_institution_jobtitles.job_title_id AS id 
    FROM k12_dms_contacts_institution_jobtitles 
      INNER JOIN k12_dms_institution_master ON k12_dms_institution_master.id = k12_dms_contacts_institution_jobtitles.inst_id 
    WHERE (
       k12_dms_institution_master.state_id='63' 
       AND (select count(disctinct k12_dms_contacts_institution_jobtitles.glevel_id) from k12_dms_contacts_institution_jobtitles where k12_dms_contacts_institution_jobtitles.glevel_id in ('1','2','3','4')) = 4 
      ) 
    GROUP BY 
      k12_dms_contacts_institution_jobtitles.job_title_id