Query duplicate records

delete duplicate records

  delete from t_assets_collect where aai_id in(
		select aai_id from (select row_number() over(partition by aai_tag_number order by t.last_update_time  desc) row_renum,t.* from t_assets_collect t)  where row_renum>1)

quote

http://www.cnblogs.com/252e/archive/2012/09/13/2682817.html

http://soft.chinabyte.com/database/308/12346308.shtml