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Junior Member
 
Group: Forum Members
Last Login: 8/20/2009 2:09:13 PM
Posts: 22,
Visits: 21
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Hello all,
I am having trouble understanding difference select * from TABLE X or select a , b, c ( columns) from table X ( same table ) above.
I was wondering if someone actually knows what is the difference at the Teradata DB Architecture level.
Thanks,
Aditi
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Forum Member
Group: Forum Members
Last Login: 2 days ago @ 7:45:03 AM
Posts: 39,
Visits: 169
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There would be slight performance improvement when you use explicit list of columns in SELECT stmt, instead of having ‘*’, but I don’t think there is any difference at DB Architecture level
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Supreme Being
Group: Forum Members
Last Login: 10/8/2009 1:16:14 PM
Posts: 79,
Visits: 105
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Hi,
AFAIK there will not be any performance difference between "select * " and "select column_lists", since the optimizer will generate same plan for both the query.
Regards,
Balamurugan
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Junior Member
Group: Forum Members
Last Login: 11/11/2009 1:12:32 PM
Posts: 14,
Visits: 39
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You can use sel top10* from table to get quicker result sets, instead of going for sel * from table , if you want to check the columns and their names, for one instance. Fetch time will be minimized.
-Thank you
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