android - MySQL relation and entities -

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i have 2 tables: place , discount n<->n relation. have table called place_discount has 2 foreign keys (idplace , iddiscount).

when add discount place, e.g. discount bar, add in place_discount table.

so issue is: have android app queries on database. when want list places have loaded, want show star on have discount. list select * place. there way query?

tip: can not use triggers because not have super privileges.

why not use join?

select   place.*,   if(ifnull(min(place_discount.iddiscount),0)>0,1,0) hasdiscount place left join place_discount on place.id=place_discount.idplace group place.id

will give 1 in hasdiscount if discount available, 0 if not.

on side note: not need super privilege trigger on table own.


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