Subject | Re: [Firebird-Architect] Re: Some benchmarks about 'Order by' - temporary |
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Author | Ann W. Harrison |
Post date | 2006-09-23T19:38:50Z |
Err, actually, Jim and I just talked about the way sort works,
and unless something has changed, nothing is "moved around on
disk". When a sort run is larger than the memory allowed, it
is written out in sorted order. When all records have been
sorted, the runs are merged. If that's right, then runs are
both read and written sequentially, which seems like the best
of both worlds... given that you've got a world where the
sorted set doesn't fit in memory.
Where have I gone wrong?
Regards,
Ann
and unless something has changed, nothing is "moved around on
disk". When a sort run is larger than the memory allowed, it
is written out in sorted order. When all records have been
sorted, the runs are merged. If that's right, then runs are
both read and written sequentially, which seems like the best
of both worlds... given that you've got a world where the
sorted set doesn't fit in memory.
Where have I gone wrong?
Regards,
Ann