G
gus
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> On Mar 2, 2016, at 4:20 PM, Thomas Mercer-Hursh wrote: > > Gus, how true is this in practice. I can see that, if one is doing a table scan regularly and there is a benefit in doing the table scan in the order of a particular index, that the performance would be better if the physical layout matched the logical one. in practice, here is a real example from a production system i did last Sunday: two tables of almost the same size. table 1 has 60,367,550 rows with 4.7 GB of data. table 2 has 56,560,647 rows with 3.4 GB of data. binary dump of table 1 takes 13 minutes binary dump of table 2 takes 86 minutes the worst case is /much, much, much/ worse than this. fortunately it is not common.
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