On Oct 29, 2010, at 7:38 AM, Igor Neyman wrote:
>> is my intuition completely off on this?
>> best regards, ben
> If your SELECT retrieves substantial amount of records, table scan could
> be more efficient than index access.
> Now, if while retrieving large amount of records "WHERE clause" of this
> SELECT still satisfies constraints on some partition(s), then obviously
> one (or few) partition scans will be more efficient than full table scan
> of non-partitioned table.
> So, yes partitioning provides performance improvements, not only
> maintenance convenience.
my impression was that a *clustered* index would give a lot of the same I/O benefits, in a more flexible way. if you're clustered on the column in question, then an index scan for a range is much like a sequential scan over a partition (as far as i understand.)
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