extension of SQL::Abstract with more constructs and more flexible API

 Sql::Abstract::More generates SQL from Perl datastructures. This is a
 subclass of SQL::Abstract, fully compatible with the parent class, but with
 some additions:
 .
 1) additional SQL constructs like -union, -group_by, join, etc;
 .
 2) methods take arguments as named parameters instead of positional
 parameters, so that various SQL fragments are more easily identified;
 .
 3) values passed to select, insert or update can directly incorporate
 information about datatypes, in the form of arrayrefs of shape [$value,
 \%type].