New FreeBSD package system (a.k.a. Daemon Package System (dps))

[Ivan Voras]

Dag-Erling Smørgrav wrote:
> Ivan Voras <ivoras at fer.hr> writes:
>> You can inspect s sqlite database with the provided utility. Unless the
>> database gets corrupted (which it tries to avoid by respecting ACID),
> 
> ACID is not something a database "respects", it is a set of guarantees
> that it provides to the application.  Avoiding database corruption is
> a necessary requirement for, rather than a consequence of, ACID.

I'm thinking of ACID as a set of ideas / procedures, the consequence of 
which is avoiding corruption. Of course, there's a "hierarchy of 
reliability" - the db relies on the file system to meet the 
requirements, the file system relies on the hardware, etc. but if the db 
doesn't make use of those, it's all for nothing.

> Perhaps you mean that SQLite tries to avoid database corruption by using
> locks, and either scatter-gather writes or copy-on-write, and flushing
> the file between transactions, to ensure consistency?

It uses locks, a journal file (for DML transactions), and flushes data 
between transactions. More info at: http://www.sqlite.org/lockingv3.html

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