MVP's and the like
I am looking for suggestions , confirmation
Let me start by saying bar none, performance is paramount with the
queries to be retured off this view/table query.
To that end I am completley donormailzing the data into a view (or a
table) with all possible legal combinations ( I have seen this reffered
to as Croation Method ?) Its ends up at 3 total rows per account on
average.
THis query is to be executed only from the web, so once again the
performance is paramount.
Ok here is what I have so far I have a set of related tables 5 or so
that are for the most part 1 to 1 but in the case of one particular
table its an average raqtion of 20 to 1.
Broken all out with 150k customer rows it ends up at 500k total rows in
the view
About 7 cols are dynamic aggregates (Sum(tran_AMT)) , min(tran_amt) ,
etc
I had it in a view and with 1/5 million rows (In the view) it performed
adequatley, I will most likeley get to somewhere around 10 million
total rows (In the view)
I looked into indexing it but thats not going to happen because I am
doing several subquery's , outer joins etc.
The View with a Select * returns in 40 Seconds
Now i ran into an issue with recursing this query into several seperate
subqueries and hit the 256 table limit, after only about 15 recursions.
Now the data only gets updated once , perhaps twice a day, in a batch
transaction.
So I Put all the data from the view into a table, and indexed that, I
can return all rows in 12 seconds and any refining conditions I throw
at it, like Date > 12/1/2003 (then it executes in under 6 second_ only
slices the query time down big time (A very good thing)
Since its only updates 2x a day I drop and recreate the table in my DTS
, and I have triggers on the other tables for Online updates (usually
no more that 100 a day) but to ensure the table is ALWAYS current it
gets recreated on import of additional rows.
Is there a name to this maddness ? My co-workers aree leary of it but
they come from a dbase background, denomailzing it into a table and
then indexing the table I couldnt be happeier with ther performance.
Are there any lurking gremlins in this design ?
I cannot see any pitfalls with doing this , or are there some ?,
basically I am denomailizing for read-only query performance.
They are concerned about the denorilization for performance, even
though its only on a read only table (was and could be a view I just
cant index this particualr view)
So I guess Im looking for a , "Sounds OK" or "Sounds Great" from the
SQL Gods ....
Chris 2 1659
WertmanTheMad (cw******@webchamps.com) writes: Since its only updates 2x a day I drop and recreate the table in my DTS , and I have triggers on the other tables for Online updates (usually no more that 100 a day) but to ensure the table is ALWAYS current it gets recreated on import of additional rows.
Is there a name to this maddness ? My co-workers aree leary of it but they come from a dbase background, denomailzing it into a table and then indexing the table I couldnt be happeier with ther performance.
Are there any lurking gremlins in this design ?
I cannot see any pitfalls with doing this , or are there some ?, basically I am denomailizing for read-only query performance.
They are concerned about the denorilization for performance, even though its only on a read only table (was and could be a view I just cant index this particualr view)
There is too little information in your post, to give any absolute blessing
to this. But with the outline you give - source data updated twice,
aggregating the data into a read-only table could very well be the winner.
The alternative would be to look into the underlying query, and see if
indexes etc can be improved. Without knowledge about the table and the
queries, I cannot say whether this is workable or not.
--
Erland Sommarskog, SQL Server MVP, es****@sommarskog.se
Books Online for SQL Server SP3 at http://www.microsoft.com/sql/techinf...2000/books.asp
> The alternative would be to look into the underlying query, and see
if indexes etc can be improved. Without knowledge about the table and
the queries, I cannot say whether this is workable or not.
Yeah, unfortunatley there are about 10 subqueries in the view and 5 or
so outer joins, Indicies on the View are a No-Go hence I ended up here.
Erland Sommarskog wrote: WertmanTheMad (cw******@webchamps.com) writes: Since its only updates 2x a day I drop and recreate the table in my
DTS , and I have triggers on the other tables for Online updates
(usually no more that 100 a day) but to ensure the table is ALWAYS current
it gets recreated on import of additional rows.
Is there a name to this maddness ? My co-workers aree leary of it
but they come from a dbase background, denomailzing it into a table and then indexing the table I couldnt be happeier with ther
performance. Are there any lurking gremlins in this design ?
I cannot see any pitfalls with doing this , or are there some ?, basically I am denomailizing for read-only query performance.
They are concerned about the denorilization for performance, even though its only on a read only table (was and could be a view I
just cant index this particualr view) There is too little information in your post, to give any absolute
blessing to this. But with the outline you give - source data updated twice, aggregating the data into a read-only table could very well be the
winner. The alternative would be to look into the underlying query, and see
if indexes etc can be improved. Without knowledge about the table and
the queries, I cannot say whether this is workable or not.
-- Erland Sommarskog, SQL Server MVP, es****@sommarskog.se
Books Online for SQL Server SP3 at http://www.microsoft.com/sql/techinf...2000/books.asp This thread has been closed and replies have been disabled. Please start a new discussion. Similar topics
by: Richard Holliingsworth |
last post by:
Hello:
I have an Access 2K form I built from a SQL Server 7.0 view. I want to
lock certain fields in the database from users so they can see them on
the views and forms, but NOT be able to edit...
|
by: Ryan |
last post by:
I have a very complex view which we've been working with for some
time. As we have progressed with this view, we have reached the stage
where the data is generated into a table which is then used...
|
by: Fran?ois Bourdages |
last post by:
Hi is there a way to know if object (view, function, etc) are invalid
?
let say a have a table t1 (field col1, col2)
and a view v1 (field t1.col1, t1.col2)
if I drop t1.col2, the view v1 is not...
|
by: brendan_gallagher_2001 |
last post by:
Hi,
I have a view(A) and I am trying to do a join on another table (B) to
include only rows where date values in view A is greater than in table
B. I also want the view to pick up rows in viewA...
|
by: xeqister |
last post by:
Greetings,
I would like to know whether there is a way to estimate/calculate
the view table size in DB2. As what I understand, view is just a
logical table and we cannot simply calculate the size...
|
by: Justin |
last post by:
I am creating a web app for a client in VS.NET using ASP.NET with C#. I need
to query three tables in a database using one parameter and display the
results on the page. my question is should I use...
|
by: Beowulf |
last post by:
I have the view below and if I use vwRouteReference as the rowsource
for a combo box in an MS Access form or run "SELECT * FROM
vwRouteReference" in SQL Query Analyzer, the rows don't come through...
|
by: Matik |
last post by:
Hey,
First, sorry if this post appear twice, because, I can not find my post
recently send, trying to post it once again.
I'm out of ideas, so, I thought, will search help here again :(
I'm...
|
by: randy.buchholz |
last post by:
Been fighting this one for a while, looking for help.
I have a simple page with a grid view and details view (just managing a
single table). The details view is primarily used for creating new...
|
by: Charles Arthur |
last post by:
How do i turn on java script on a villaon, callus and itel keypad mobile phone
|
by: emmanuelkatto |
last post by:
Hi All, I am Emmanuel katto from Uganda. I want to ask what challenges you've faced while migrating a website to cloud.
Please let me know.
Thanks!
Emmanuel
|
by: Sonnysonu |
last post by:
This is the data of csv file
1 2 3
1 2 3
1 2 3
1 2 3
2 3
2 3
3
the lengths should be different i have to store the data by column-wise with in the specific length.
suppose the i have to...
|
by: Hystou |
last post by:
There are some requirements for setting up RAID:
1. The motherboard and BIOS support RAID configuration.
2. The motherboard has 2 or more available SATA protocol SSD/HDD slots (including MSATA, M.2...
|
by: Hystou |
last post by:
Most computers default to English, but sometimes we require a different language, especially when relocating. Forgot to request a specific language before your computer shipped? No problem! You can...
|
by: Oralloy |
last post by:
Hello folks,
I am unable to find appropriate documentation on the type promotion of bit-fields when using the generalised comparison operator "<=>".
The problem is that using the GNU compilers,...
|
by: jinu1996 |
last post by:
In today's digital age, having a compelling online presence is paramount for businesses aiming to thrive in a competitive landscape. At the heart of this digital strategy lies an intricately woven...
|
by: Hystou |
last post by:
Overview:
Windows 11 and 10 have less user interface control over operating system update behaviour than previous versions of Windows. In Windows 11 and 10, there is no way to turn off the Windows...
|
by: agi2029 |
last post by:
Let's talk about the concept of autonomous AI software engineers and no-code agents. These AIs are designed to manage the entire lifecycle of a software development project—planning, coding, testing,...
| |