How to form a correct query in a linked table?

Question

MySQL

Let's say there are 3 tables: Products, Attributes, Attribute_values ​​(linked to the other two by attribute/product_id).
There are 2 products - Computer chair and Armchair
There are 3 Attributes - Backrest, Armrests, Adjustable height.
And the question is: How to pull out products that have all 3 attributes available (= 1) through an adjacent table? (only a computer chair should turn out)

Answer 1

Like this, for example (this is T-SQL):

select P.*
  from Products as P
  join Attribute_values as AV
    on AV.ProductID = P.ID
   and AV.Value = 1
   and AV.AttributeID in (attr1, attr2, attr3)
 group by P.*
having count(AV.ID) = 3

Well, of course the ProductID/AttributeID combination in Attribute_values ​​must be unique.