MySQL query, intersection on many-to-many relationship -

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does have idea/solution how achieve this?

situation is: have tables 'releases' , 'ntags', related via 'releases_ntags' (containing 'release_id' , 'ntag_id')

and fetch results releases via ntag's 'slug'.

i manage have semi-working:

sql

select r.id, r.name releases r left join ntags_releases rt on rt.release_id = r.id join ntags nt on nt.id = rt.ntag_id , (nt.name = ('tag_1') or nt.name = ('tag_2')) group r.id, r.name

so far good, gives me releases "tag_1" plus releases "tag_2" (and off course both tags).

but need intersection of tags, say:

"releases 'tag_1' and 'tag_2'"

so tried with:

... , (nt.name = ('tag_1') , nt.name = ('tag_2')) ...

but leads in empty result. have idea how achieve this? don't know how go further on , appreciate input!

thx

you can demand 2 distinct ntags present in having clause:

select  r.id, r.name    releases r join    ntags_releases rt on      rt.release_id = r.id join    ntags nt on      nt.id = rt.ntag_id   nt.name in ('tag_1', 'tag_2') group         r.id, r.name having         count(distinct nt.name) = 2

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