Subject Re: [Firebird-Architect] for discussion Transient Data Set
Author Ann W. Harrison
Leyne, Sean wrote:

> Why not store them in the database file itself?

Two reasons. Clean-up and performance. The performance reason is that
the temporary file could be a RAM file, which the database can't. The
clean up of a temporary file is instant and automatic.

> As I see it, it would simplify the implementation since the engine would
> see the TDS just like a real table (registered in RDB$RELATIONS), and
> all existing table functionality would be supported.

After the first reference, the engine gets all its information from the
Relation objects and their various relatives. The system tables are a
bootstrap mechanism. The earlier discussion of temporary tables
provides a general architecture for mapping a relation to a different file.