--SQL删除重复记录 保存其中一条
delete CodeID where Code Not In( select min(Code) from [CodeID] group by ID)
-- SQL查询 最多只显示两条数据
select min(code),id from codeID group by ID
union
select max(code),id from codeID group by ID
--SQL删除重复记录 保存其中一条
delete CodeID where Code Not In( select min(Code) from [CodeID] group by ID)
-- SQL查询 最多只显示两条数据
select min(code),id from codeID group by ID
union
select max(code),id from codeID group by ID