the clutter with explains .Just what is it and how to avoid that : Redistribution and Duplication

Database

the clutter with explains .Just what is it and how to avoid that : Redistribution and Duplication

Hi Folks
I am still confused about just how this stuff , regards finding out whats happens in query explains , works.
I kind of get the broad picture but am not really able to extract a precise of meaning of things when I read some typical steps in explains.
AMP Duplication and Duplication. Can someone help me visualize that better and how can we avoid each of these steps if these are taking a lot of time to finish off . Any resources where we c an find some dope on these is appreciated.
Thanks !!!
Doug
1 REPLY
Teradata Employee

Re: the clutter with explains .Just what is it and how to avoid that : Redistribution and Duplication

Use Visual Explain or Query Analysis Facility (QAF). Redistribution happens when your query is joining tables on non-primary index columns. You may want to rewrite your queries so that you join on primary index columns first before on non-primary index columns.