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On 08/25/07 21:51, Kevin Kempter wrote:
> Hi List;
>
> I have a very large table (52million rows) - I'm creating a copy of it to rid
> it of 35G worth of dead space, then I'll do a sync, drop the original table
> and rename table2.
What is your definition of "dead space"?
Bad rows, duplicate rows, old rows? Something else?
> Once I have the table2 as a copy of table1 what's the best way to select all
> rows that have been changed, modified in table1 since the initial laod from
> table1 into table2?
>
> Also I'll need to delete any rows in table2 that no longer remain in table1.
>
> There is no change date column
> I could do something like select * from table1 where col1 || col2 || col3 etc
> not in (select col1 || col2 || col3 etc from table2)
>
> but this would be ineffecient & slow.
>
> Anyone have a suggestion to do this in an efficient manner?
>
> Thanks in advance
- --
Ron Johnson, Jr.
Jefferson LA USA
Give a man a fish, and he eats for a day.
Hit him with a fish, and he goes away for good!
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