[postgis-devel] postgis_upgrade.sql

[Mark Cave-Ayland]

strk wrote:

> The nice thing of current upgrade script (if I haven't missed later
> changes) is that it's autogenerated, so no maintainance required.
> The other nice thing is you can keep feeding it to your database
> to swich between postgis versions (even if it's just to change
> path to the library).

Unfortunately this means that any generated script is tied to a 
particular installation; so if you have different databases in different 
states of upgrade broken-ness, you need to regenerate any upgrade .sql 
files for every single installation that can be different; not cool.

At least with tighter upgrade procedures in place from 1.4, then after 
an upgrade it would just be a case of running the relevant .sql script 
after "make install" and everything would work just fine.

Another good reason to just have plain .sql upgrades is that all of the 
upgrade scripts are written in perl, and Win32 users don't have perl 
available by default. Hence Win32 upgrades can be a complete nightmare 
if you're new to all of this.

At the end of the day, the cost comes down to developers having to add 
changes to an upgrade file as we go along, for the benefit that upgrades 
are well-documented and much easier to do for users. And I believe that 
it will be beneficial for all of us in the long run to make the upgrade 
cycle as painless as possible.


ATB,

Mark.

-- 
Mark Cave-Ayland - Senior Technical Architect
PostgreSQL - PostGIS
Sirius Corporation plc - control through freedom
http://www.siriusit.co.uk
t: +44 870 608 0063