Issue with mysql multiple left join and group by -


well got 3 tables:

tb1:

tb1_id pk tb1_name 

tb2:

tb2_id pk tb1_id fk 

tb3:

tb3_id pk tb2_id fk 

and got query:

select a.tb1_nome       ,b.tb2_id       ,count(c.tb2_id) lins   tb1        left join tb2 b on a.tb1_id=b.tb1_id        left join tb3 c on b.tb2_id=c.tb2_id   group b.tb2_id order a.tb1_id desc 

but doesn't returns rows of tb1.

i got 3 tables need get rows of tb2 matches tb1 , show count of rows of tb3 matches tb2

i think need use inner join instead of left join. inner join selects rows has records on table joined. give try , have feed later :)

select  a.tb1_name,         b.tb2_id,         count(c.tb2_id) totalcount    tb1            inner join tb2 b              on a.tb1_id = b.tb1_id           inner join tb3 c              on b.tb2_id = c.tb2_id group a.tb1_name, b.tb2_id order a.tb2_id desc 

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