Database Upgrade Complete!

PostGIS 1.5 has delivered new geography types (lat/lon) and associated spherical based functions, operators and indexes.  We have previously used PostGIS geometries for both large scale dataset boundaries, and global Earth-Tile grid, but had knowingly incurred edge cases in which a search of Indian Ocean may predictably return a small number datasets crossing the IDL due to the planar coordinate system used (SRID=-1).

We've desired to fix this for some time and decided to perform a full database migration (approx 10^5 datasets and 10^8 tiles), which has been some weeks in testing to iron out stumbling points in the "hard" data migration.  The migration procedure can be seen here.

In doing this we've also taken the opportunity to bump the Postgresql version to 8.4 series, shifted to UTF-8 encoding (previously unencoded SQL_ASCII) and reworked onto a full 64 bit software stack.  

The results are quite impressive and worth the considerable time taken.