Hi folks, I don;t know if it's cos it's Monday or what, but I can't see what's wrong here.
I've got two tables, turns which holds a turn number, a task, and where appropriate a link to a loco. The select below works but only shows those tasks where a loco is involved.: select r.rtid, concat(r.rcid::text || ' on ' || l.lnumber::text) as task from rides r, loco_dets l where r.rlid = l.lid group by rtid; rtid | task ------+--------------------------------------------- 5 | G on 60007 6 | A on 75014, C on 75014, A on 75029, C on 75029 7 | C on 4277, A on 44767, C on 44767 8 | A on 30926, C on 30926, G on 60532 9 | A on 30926, C on 30926, A on 75014, C on 75014 10 | F on 2392, F on 75029, L on 75029 11 | A on 44767, C on 44767, A on 75029 However, when I tried to change this to using an outer join I'm getting stuck. Can anyone see my stumbling point, which I think is to do with the condition part of the case statement. Do I need to do that in a sub-select first or is there an alternative? =# select r.rtid, -# case when r.rlid > 0 then -# concat(r.rcid::text || ' on ' || l.lnumber::text) -# else -# r.rcid::text -# end as task -# from rides r -# left outer join loco_dets l on r.rlid = l.lid -# group by rtid -# order by rtid -# ; ERROR: Attribute r.rlid must be GROUPed or used in an aggregate function =# -- Gary Stainburn This email does not contain private or confidential material as it may be snooped on by interested government parties for unknown and undisclosed purposes - Regulation of Investigatory Powers Act, 2000 ---------------------------(end of broadcast)--------------------------- TIP 8: explain analyze is your friend
