a confusion regarding package updates

[Tom H]

On Wed, Jan 19, 2011 at 8:56 AM, Alan Pope <popey at ubuntu.com> wrote:
> On 19 January 2011 13:09, Tapas Mishra <mightydreams at gmail.com> wrote:
>>
>> When it says intelligently handles changing dependencies with new
>> version of packages then what does it mean?
>> Is it referring to moving from 10.04 to 10.10?
>
> Yes and no.
>
> apt-get dist-upgrade _can_ be used as one of the tools to get you from
> 10.04 to 10.10. However so long as you haven't changed your
> sources.list, you'll stay on whatever release you're currently on.

In Debian, do-release-upgrade doesn't exist so an upgrade is performed
by making some preparatory changes including changing
"/etc/apt/sources.list" and running "apt-get upgrade" or "aptitude
safe-upgrade" for a "minimal system upgrade" before upgrading the
entire system. The same definitely applies to Ubuntu so as not to
introduce too many changes in one go if you choose not to use
do-release-upgrade.