update tablename
set picvar=iif(picvar=2,6,picvar-1)
where picvar between 2 and 6
update tablename
set picvar=iif(picvar=2,6,picvar-1)
where picvar between 2 and 6
update tablename
set picvar=iif(picvar=2,6,picvar-1)
where picvar between 2 and 6
update tablename
set picvar=iif(picvar=2,6,picvar-1)
where picvar between 2 and 6
picvar=6
eles
picvar=picvar-1
end if
---vb的解释
update img set picvar=picvar-1 where picvar>=2 and picvar<6，但是我这条对数据库操作总是不成功