mysql - FInd the names of customers are interested in every artist -

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i looking customer names of customers have interest in artists.

i understand in relational algebra, can use division operator, not understand sql format in doing so.

i have these tables columns:

customer (customerid, firstname, lastname) artist (artistid) customer_interest_in_artists (artistid, customerid)

how go doing this?

you using simple min() construct:

select c.firstname, c.lastname, min(ci.customerid not null) interest_all artist left join customer_interest_in_artists ci using (artistid) left join customer c using (customerid) group c.customerid having interest_all = 1

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