How to do this query?

Hi,

i'm a newbie in sparql and trying to do same queries, but i'm not getting
the results that i won't. I have a owl file and i'm trying to create a query
that returns a determinated class, in sql i would do "select * from X where
meat=pig" how do i do this in sparql??

Do you know any tutorial that can help me give the firsts steps?


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Samuel Pedro