Re: Stored Procedure Speed/Visual Explain

Hi Alan

No, common table expressions are like views, and we usually use them in joins in a SELECT - same as nested table expressions, but CTEs are maybe easier to work with, since they are separate from the main SELECT.

So part of the recommendation is to use CTE/NTE or to use views.

Vern

On 10/21/2013 9:09 AM, Alan Cassidy wrote:

On Fri, Oct 18, 2013 at 2:04 PM, Vernon Hamberg <vhamberg@xxxxxxxxxxxxxxx>wrote:

Was just at RPG-DB2 Summit - we are encouraged to put as much into a
single SELECT statement as we can, by the IBMer, Tom McKinley, who did
a presentation on set-based thinking with SQL.

Tom specifically said to avoid multiple steps of putting data into
separate tables in QTEMP. instead, look for ways to combine as JOINs
or maybe as IN predicates against a subquery.

Do common table expressions count as "separate tables"?

Alan

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