Subject Re: [Firebird-Architect] Supported transaction isolation levels?
Author Thomas Steinmaurer
Hi Ivan,

>>Looking through different Firebird related documentations (Helen's book,
>>IBP pdf set, ...), it seems that Firebird doesn't support the
>>SQL-compliant transaction isolation level "REPEATABLE READ". Is this
> Yes. SQL standard tries to avoid specifying any implementation
> details (like indexes that influence performance but not the result),
> but it fails in case of transaction isolation levels, because it describes
> lock-based databases and completely "forgets" multi-version databases.

The weird thing now is that the MySQL folks claim that the InnoDB table
type supports ACID-compliant transactions with all four isolation levels
and even support of the MVCC model. Well, this is off-topic here, but I
do find it somewhat strange.

> The isolation levels are somewhat similar, but not equivalent.