遍历含有标识列的表

declare @identityColumn int --记录当前要修改的标识列
select @identityColumn=min(identityColumn) from tablename
while @identityColumn is not null --遍历修改标识列
begin
 update tablename
  set identityColumn=identityColumn*2 --比如修改标识列为原来的2倍，也可修改其他列
  where identityColumn=@identityColumn

 select @identityColumn=min(identityColumn) from tablename
  where identityColumn>@identityColumn
end