select max(fid) as fid from
(
select max(fid) as fid from A where id='34483' union select max(fid) as fid from B where id='34483'
)tmp
或
select max(fid) as fid from
(
select * from A
union all
select * from B
) tmp
where id='34483'
(
select max(fid) as fid from A where id='34483' union select max(fid) as fid from B where id='34483'
)tmp
或
select max(fid) as fid from
(
select * from A
union all
select * from B
) tmp
where id='34483'
(
select max(fid) as fid from A where id='34483' union select max(fid) as fid from B where id='34483'
) tmp
select max(fid) as fid from A where id='34483' union select max(fid) as fid from B where id='34483') as tmp order by fid desc