we have associative table connects threads tags. trying figure out query give thread id's tied combination of tag id's. created sqlfiddle at:
http://sqlfiddle.com/#!9/c8ebe/3
so table structured this:
create table `threads_tags` ( `id_threads` bigint(20), `id_tags` bigint(20) ); some sample data may this:
id_threads id_tags 2 12 4 12 9 10 2 21 3 2 2 1 5 1 5 21 in our example, have tag id's 12 , 1 , need query return 2 id_threads because id_threads has both id_tags = 12 , id_tags = 1. there no limit number of tags may need match against. think need using relational division , tried using query:
select id_threads threads_tags tt1 id_tags in (1,12) group id_threads having count(*) = ( select count(*) threads_tags tt2 id_threads = tt1.id_threads ) it doesn't seem working though. thought using solution @ relational division in mysql without aggregrate functions? in example, not sure put list of id_tags want input query. new @ relational division type of queries can give me here appreciated.
this should you're looking for:
select id_threads threads_tags id_tags in (1,12) group id_threads having count(distinct id_tags) = 2; the number 2 after having count... number of values in list (in case it's 2 - 1 , 12).
