Discuz版块的内容，主要放在cdb_posts这个表中，通过select * from cdb_posts where fid=15 and first=1 and invisible=0即可，其中fid为版块id
Discuz主题分类的内容，要通过cdb_threads和cdb_posts相结合，通过
select * from cdb_threads as a, cdb_posts as b WHERE a.typeid=12 and a.fid=2 and a.tid=b.tid and b.first=1 and b.invisible=0 order by b.tid desc
其中fid为版块id，typeid为主题分类id
