【DB2】NULLS LAST与NULLS FIRST

DB2函数配合 
select row_number() over(order by col desc nulls first/nulls last ) as rn,col from table1order by rn; 
nulls first:把空值放到最前面,再对非空值排序 
nulls last:把空值放到最后面在对非空值排序

原文地址:https://www.cnblogs.com/OliverQin/p/9207080.html