select * from (select jcrxm, count(jcrxm) as cnt from JCXS_INFO where (jcrq between ? and ?) and jcsd like ? group by jcrxm order by cnt desc) t where t.rownum <= 2

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探讨

还是不行啊，提示错误无效的用户，表，列或列规格
语句这样写的set   rsk=cn.execute(( "select   *   form   (select   jcsd，jcrq，jcrxm，count(jcrxm)   as   cnt   from   jcxs_info   where   jcrq   between？   and   ？   and   jcsd   like ……