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Thread: Need query

Need query

From
Gaurav Jindal
Date:
Can anybody help me with query-

I have 3 tables- a,b,c

a has relation with b and b has relation with c
a does not have a relation with c 


I need to find top performing item in table 'a'. It is based on count. If more count, it is top performing. We can count only based on actions in table 'c'. I can put 'where' clause in table 'c' and find those values. I can't join table 'a' and 'c' as they don't have any relation. 


select b.top 
FROM b,c
WHERE c.action IN ('blah', 'blah', 'any values')  and b.id = c.id;

'top' in the query is a common column  in table 'a' named 'a_top'. We need to count column 'track' in table 'a' based on this information.

Re: Need query

From
David G Johnston
Date:
Gaurav Jindal wrote
> a has relation with b and b has relation with c

Given this statement what specifically are you having difficulty with.  You
are allowed to perform multiple joins, whether explicit or via FROM/WHERE,
in the same query.

SELECT ...
FROM a,b,c
WHERE a=b and b=c

OR

SELECT ...
FROM c
JOIN b on c=b
JOIN a ON b=a

David J.





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