"Firebird 2.0 brings a large collection of long-awaited
enhancements that significantly improve performance, security and
support for international languages and realise some desirable new
SQL language features. Under the surface, it also provides a much
more robust code platform from which the re-architecting planned
for Firebird 3.0 is proceeding.
"Several limitations inherited from the legacy code have now
gone, such as the 252-byte limit on index size and sub-optimal
usage of index statistics that could throttle performance. Table
size is no longer limited to 30 Gb..."