当前
select * from tbl_name where id='$id'上一条
select * from tbl_name where id<'$id' order by desc limit 1下一条
select * from tbl_name where id>'$id' order by limit 1
select * from tbl_name where id='$id'上一条
select * from tbl_name where id<'$id' order by desc limit 1下一条
select * from tbl_name where id>'$id' order by limit 1
然后
select * from tbl_name where id='$lastId'
select * from tbl_name where id='$nextId'