[postgis-users] Simplifying Adjacent Polygons

[Ben Madin]

G'day all,

Is there any way to simplify adjacent boundaries so that they remain congruent?

By way of explanation, I have finally obtained / cleaned up a data layer for administrative boundaries in mainland South-East Asia, and I am very happy with the result - all the topology etc is correct. I have tried to maintain the high level of resolution etc so that when I zoom in (using web / mapserver / qgis / whatever) it looks great and matches up with rivers etc. 

However, for analytical purposes, loading it into R takes about 5 minutes of dual processor stress. And realistically, for these purposes I don't need this level of detail. (vector output images are also unwieldy)

So off I go to using st_simplify / st_simplifypreserve topology, which does exactly what it claims to do... but now I have terrible (looking)  gaps between adjacent boundaries.

So, is there any way to simplify adjacent boundaries so that they remain congruent? 
(I have a suspicion I may finally have to learn what the terms simple features and topological GIS really mean...)

cheers

Ben