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Base de données, Tables, Vues, Index et syntaxe SQL
Hi
>If a query with a small result set is not based on a good selectivity
but a full table scan and a grouping operation , it cannot be fast, IMO.
If that is the case, I'ld opt for the xBase - solution.
This would get [relatively] better the larger the rowsize of
b.cfk1, b.cfk2, a.ctype
really is, since no temp table to later group on is needed.
Simulating group by in xBase is not that hard <g>,
and even scanning the whole "many" shouldn't take more than 10 secs,
if the rowsize/hardware of the "many" allows fast throughput.
Processor speed nearly irrelevant here, I/O bottleneck IMHO.
But without better info this is just shooting in the dark.
my 0.02 EUR
thomas
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