ISPconfig is a great package which is adopted by most newer bsd and linux ISP's. Due to the problems for mysql from Oracle buying up innodb and berkeley db, postgresql is starting to move far ahead in terms of development. The FUD generated by Oracle's purchases is hitting home in businesses worldwide. Unless I am terribly mistaken, postgresql is the ONLY open source database which can't be sold out to commercial vendors, because of copyright retention. It is the only guaranteed database platform for community-based open source future.
The postgresql folks are investing heavily in making OpenOffice an automatic user of postgresql on windows (where it is now running natively) and on both bsd and linux servers. Infoworld has stories every month about how folks who started with mysql are now upgrading to postgresql. Postgresql has also become the open source standard for data warehousing, business intelligence and data analysis stacks.
I honestly believe that if ispconfig supported postgresql as an automatic option, supporting client databases, and connecting to the backend it would be met with great success. Most of the code to do it is already out there in places like pgadmin and webmin.
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