sql - How do I group by using an average? -


i need display names of business has average quantity of less or equal 300.

table s:

busname     busnum  -------   ---------   bob        a1       lee        a2         ashley     a3

table sp:

busnum     qty  -------   --------- a1         300     a1         400      a1         100  a2         100 a2         100 a2         200 a3         400 a3         300

this i'm trying:

select s.busname s s join sp p on p.busnum = s.busnum group s.busname having avg(p.qty) <= 300;

select busnum , average of qty table sp temporary table, normal join! can do:

select s.busname s, (select busnum, avg(qty) average          sp          group busnum) temporal s.busnum = temporal.busnum , temporal.average <= 300;

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