XPS questions

I have been doing some reading on XPS and some questions on how things work have occurred to me. I have skimmed through all the manuals I could find and not found this information, if it is contained in a manual, please point me in the right direction. Question 1. Is the result set for a particular query just stored in a temp table in the connection co-server until all the data is finally retrieved? Question 2. How does XPS handle joins across coservers It looks like each coserver does as much of the join as possible and then it must pass the work back on to the connection co-server for processing to complete. Here is an excerpt from the manual -- For example, consider the following SQL request: SELECT geo_id, sum(dollars) FROM customer a, cash b WHERE a.cust_id=b.cust_id GROUP BY geo_id ORDER BY SUM(dollars) In this example, the connection and participating coservers perform thefollowing tasks: 1. Each coserver scans relevant fragments of the customer table and the cash table in parallel. 2. Each coserver joins rows from local fragments of both the customer table and the cash table by customer ID. 3. As participating coservers complete local join operations, they can go on to perform other portions of the join operation or aggregations. They can also perform some of the steps that are involved in selecting the geographic areas and dollar amounts that belong to particular customers, the group-by operations, and the order-by operations that are needed to complete the query. 4. When the query is complete, the connection coserver returns the results to the client. -- It seems to me that there needs to be a step 3.5, something like: coservers send data back to the connection coserver who finishes the join, sort, group by, ... operations. or coservers then pull data from the remote co-servers finishing the join operation and then pass the data back to the connection server to finish sort, group by operations... Reason behind this question. I want to understand how this works so I can recognize possible causes for slowdowns. Thanks, Will P.S. XPS is brand new to me. ------------------------------------------------------------ This e-mail has been sent to you courtesy of OperaMail, as a free service from Opera Software, makers of the award-winning Web Browser, Opera. Visit us at http://www.opera.com/ or our portal at: http://www.myopera.com/ Your free e-mail account is waiting at: http://www.operamail.com/ ------------------------------------------------------------