for the "duplicate key exception" test, make it a little more flexible, because the format of the VALUES clause varies a little depending on the type of the index.



git-svn-id: http://h2database.googlecode.com/svn/trunk@4912 e6896862-9d19-0410-bfb3-e9fa5d50e656
split up the AggregateData computation into different classes.
The purpose of this is to simplify the code for the individual cases to make it easier to implement analytic (windowing) functions.

git-svn-id: http://h2database.googlecode.com/svn/trunk@4913 e6896862-9d19-0410-bfb3-e9fa5d50e656
make some field names in Aggregate more obvious, to distinguish the special case GROUP_CONCAT fields from the normal fields

git-svn-id: http://h2database.googlecode.com/svn/trunk@4914 e6896862-9d19-0410-bfb3-e9fa5d50e656