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On Thu, Nov 10, 2011 at 2:05 PM, David Hollander <> wrote:
>> Why would I want to compare a table to a string if I've got the tables?
> The primary advantage of comparisons using a hash string over a
> _VERSION table is it works regardless of whether or not the source of
> the module is trusted. It also always works for everything, rather
> than a subset of code with _VERSION set to a table faithfully and only
> shared via HTTPS\SSH. If the fundamental reason for version identity
> is to prevent unknown state\non-determinism, the additional advantage
> of a hash string comparison is that it can also be performed before
> executing the module in question.
> The primary advantage of a number time timestamp being set upon
> redistribution over a _VERSION table, is that it is a metric
> containing more information. It signals "recentness" in addition to >,
> <, ==, and can be re-displayed in a variety of formats and orderings
> without changing the underlying information.
> - David
A timestamp is somewhat useless in many cases... unless you pair it
with other information.

Some developers maintain multiple versions of the same software over
time and do not expect everybody to hop onto the latest and "greatest"
version since there may be incompatible API... or behavior changes
that are in spirit with the project, but break assumptions that may
have been made.

Thomas Harning Jr.