左内连接时选择带分组的情况

Question

I have this code which returns the result I want;

select stktype, Part_No,
Case when stktype = 'labour' then Part_No END
from fleet_job_jobdetails
where JobCode = '176071' AND StkType = 'labour'
group by part_no, StkType

stktype Part_No (No column name) Labour ANDR ANDR

when I add it to my larger code i get error

LEFT JOIN (
           SELECT   jobcode
           ,        SUM(linecost) AS totalcost
           ,        SUM(CASE WHEN stktype = 'sublet' THEN linecost
                             ELSE 0
                        END) AS subletcost
           ,        SUM(CASE WHEN stktype = 'labour' THEN linecost
                             ELSE 0
                        END) AS labourcost
           ,        SUM(CASE WHEN stktype = 'part' THEN linecost
                             ELSE 0
                        END) AS partscost
           ,        SUM(CASE WHEN stktype NOT IN ('sublet', 'labour', 'part') THEN linecost
                             ELSE 0
                        END) AS othercost
        ,           **CASE WHEN (select StkType from fleet_job_jobdetails WHERE stktype = 'labour')  = 'labour' THEN Part_No  ELSE '' END AS Mech**
           FROM     fleet_job_jobdetails
           GROUP BY jobcode, Part_No
          ) a
        ON fleet_job_jobmaster.jobcode = a.jobcode

Answer 1

Part_No only in this case

** CASE
                       WHEN (select StkType
                               from fleet_job_jobdetails
                              WHERE stktype = 'labour') = 'labour' THEN
                        Part_No

so there will be no Part_No situation,you must revise the statement to make sure the Part_No exist and not in WHEN THEN

OR you just only group by jobcode

Answer 2

TRY THIS:

LEFT JOIN (
       SELECT   jobcode
       ,        SUM(linecost) AS totalcost
       ,        SUM(CASE WHEN stktype = 'sublet' THEN linecost
                         ELSE 0
                    END) AS subletcost
       ,        SUM(CASE WHEN stktype = 'labour' THEN linecost
                         ELSE 0
                    END) AS labourcost
       ,        SUM(CASE WHEN stktype = 'part' THEN linecost
                         ELSE 0
                    END) AS partscost
       ,        SUM(CASE WHEN stktype NOT IN ('sublet', 'labour', 'part') THEN linecost
                         ELSE 0
                    END) AS othercost
                    --Here seems subquery is not required we can simply replace with it
        ,           CASE WHEN stktype = 'labour' THEN Part_No  ELSE '' END AS Mech 
       FROM     fleet_job_jobdetails
       GROUP BY jobcode, Part_No
      ) a
    ON fleet_job_jobmaster.jobcode = a.jobcode