Re: Update statistic question
Posted in 1998
Susan
There was an interesting discussion on this subject in this forum some
weeks ago. You may want to check the archives.
Heres my take on these discussions. You could split up the script into
n parallel scripts where n=NUMCPUVPS. Make sure that each parallel
script does all the UPDATE STATS for a given table, ie dont do UPDATE
STATS MEDIUM FOR TABLE table1 in script1 and UPDATE STATS HIGH FOR
TABLE table1 in script2, as there is a chance they may step on each
other.
HTH
Sujit Pal
______________________________ Reply Separator _________________________________
Subject: Update statistic question
Author: "Susan Elliott (ISG)" <SusanE@fclcis.co.nz> at Internet
Date: 4/22/98 6:23 PM
Thanks to all of those who have been answering my questions over the
last few days !!! Its much appreciated !!!
I have a question about the Update statistics script that we do
here....
#### Beginning of script #####
set isolation dirty read;
update statistics medium distributions only;
update statistics high for table (Table name) (Column Name)distributions only;
{We do the update statistics high on 13635 tables, like above}
update statistics low;##### End of script ######
This was set up for me. I have worked out that the high over writes
the mediums on the tables/ columns specified. It does an update low
across the whole database.
Does this mean that the lows have over written the highs ???
Should I change the order of this to low, med and then to the highs ??
Or to med, low and then the highs ??
My next stumbling block is the above script runs sequentially and
takes over 2 days to complete. (we don't run it very often now) So
that we can run this more often..... and maybe we will get better
performance...
What are my options in breaking up the above script ????
What do other folk do ???
Can I just break the highs script up and run several at once ???
Can split it up into table types... general ledger, accounts payable,
sales etc and do the low, med and then the high on each table types
???
How many scripts I run at once ??? What is this dependant on ???
physical cpus ? cpu vps ??
Honestly, any help with this would be much appreciated,
Thank in advance
Best Regards
Suze.