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Hi all,
I´ve got a strange problem, hope
you could help. I´ve got a table (a ) with n tuples, and two fields
, birthplace and birth date. There´s another table ( say b) with m tuples,
where i´ve got a lot of polygons ( with their code, same as bithplace). Now i
want to make a join, to obtain how many people corresponds to each
place-polygon. I write
create table personsbyplace as select
a.birthplacecode as code,count(*) as peoplecount from a,b where
a.birthplacecode=b.polygoncode group by birthplacecode Well, what i can´t understand is why "Select
sum(count) from personsbyplace" is > than "a" row number!
(n)
In "b" i´ve got all places and "a" table is a list
of people, with their place and birth date. It can´t be greater
sum(count) than number of persons! Where is the mistake?
Thanks in advance,
Gus
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