MySQL many-to-many SELECT query -

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i have product table, tags table , table links them together, producttags.

product

id

producttags

productid tagid

tags

id

i want query producttags table productids have both tagid 1 , 2. how this?

select * producttags tagid = 1     , tagid = 2

this won't work... can't quite head round how it!

any appreciated!

this "set-within-sets" query , solve these using group by , having. here 1 method:

select productid producttags tagid in (1, 2) group productid having count(distinct tagid) = 2;

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