Transact SQL :: Partitioning Performance With 15 Min Partitions

Oct 27, 2015

We are currently developing an OLTP application, which will need to purge data when it becomes older than 1 hour.Rather than having a process which deletes rows periodically (and risks locking the tables), I am considering using partitioning on a rolling 15 minute window.The idea is to have 5 active partitions, with the 5<sup>th</sup> one being swapped out, merged and a new one split in. This will allow data to live to a max of 1 hour 15 mins,which is acceptable.

Actually, I will have 8 partitions; there will be 4 partitions set in the future, just to ensure when the last partition is split, there isn’t any data movement, as the newest partition will be empty.I am wondering if there will be any performance issues due to partition swapping, merging and splitting every 15 minutes? The application will have a high volume of users when live. I think this should be a better option that continually deleting from the tables.

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Tables Partitioning -- Performance Boost

Nov 13, 2007

Hi

I have a question about the partitioning a table.

I have a database with more 50 tables and 25 tables are having more than 10 lakhs records which includes history records.I have two data files for this database under PRIMARY FILE GROUP.Now i want to transfer these history records to some other database.
I wanted to know if this kind of activity will boost the database performance?.If yes how should i configure my new database.
On what factors of partitioning my performance will boost.

Thanks in advance

Regards
Arvind

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Can Partitioning A Table Boost My Performance?

Sep 28, 2007

I have an existing database with a table of about 50 milion records. There are also about 20 other tables, but they are alot smaller. The large table has a uniqueidentifier as it's Primary key (not sequential) and a forien key to a 'parent' table. The table also has a column telling when it was created. So, a bit simplified, it looks like:

ChildTable
---------------
Id uniqueidentifier <PK>
ParentId uniqueidentifier <FK>
CreationDate DateTime

ParentTable
-----------------
Id uniqueidentifier <PK>
CreationDate DateTime


Most of the questions accessing the Child table (the large table) is doing so by referensing the parent table, and not the CreatingDate, i.e.
SELECT *
FROM ChildTable
WHERE ParentId = '......'

All records with a specific ParentId will have very similiar CreationDates.

Now, my question is, will Partitioning the ChildTable boost performance for me? In case it will, what column(s) would define the Partitions? If I do it by CreationDate, a select-query like the one above will have to scan all partitions anyway, doesn't it? Doing it by Id isn't soo easy either I guess? If it helps, it might be possible to change the primary keys in the tables to have sequential guids.

Is there perhaps a performance tool to get help with suggestions about how to partition the table? Something like the 'Performance dashboard' reports, but for partitioning?

Regards Andreas



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Transact SQL :: Update Table With Max Value And Row Number (based On 2 Column Partitions)

Sep 15, 2015

I have 3 columns. I would like to update a table based on job_cd and permit_nbr column. if we have same job_cd and permit_nbr, reference number should be same else it should take max(reference number) from the table +1 for all rows where reference_nbr column is null

job_cd permit_nbr reference_nbr

ABC1 990 100002
ABC1 990 100002
ABC1 991 100003
ABC1 992 100004
ABC1 993 100005
ABC2 880 100006
ABC2 881 100007
ABC2 881 100007
ABC2 882 100008
ABC2 882 100008

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Transact SQL :: String Hex Comparison And Partitioning?

Oct 22, 2015

Our dev team wants to introduce a complex key, which is made up of
 
EventDate         datetime2(5)      = ‘2015-10-22 10:19:59.12345’
ConsumerID      bigint                = 1234
SiteID               tinyint               = 15

EventDate will be converted to a bigint and then to a hex value

= 2015-10-22 10:19:59.12345 = 2015102210195912345 = 1BF714C8A0D4F699

ConsumerID will be converted to a hex value

= 1234 = 4D2

SiteID will be converted to a hex value

= 15 = F

The hex values will then be concatenated together and stored as a string (varchar). The application will handle the creation of the complex key

   = ‘1BF714C8A0D4F699-4D2-F’

I am trying to argue against this approach and get them to store the values in their native form, in separate columns as a natural key.

To make matters worse, we need to use partitioning, where the partition boundary will be on a hexed datetime2(5) at weekly intervals. I was really hoping a proof of concept would show that hex string comparison could potentially put a row under a wrong partition, but so far, on an 8 million rowset, it is working fine.

For example, in the proof of concept, right partition boundary:

= '1BF398D53DFA1800' 
(2014-12-15 00:00:00.00000)

contains rows

= '1BF3983242B9C000-1-2'
(2014-12-08 00:00:00.00000-1-2)

Through to

= '1BF398C373960580-2FAF3003-2'  
(2014-12-14 23:59:00.00000-800010243-2)

The prior partition boundary is 1

= 'BF3983242B9C000'
(2014-12-08 00:00:00.00000)
 
How is this working, given that the string lengths (varchar) are different and the row value contains dashes and the partition boundaries are smaller in length without dashes? How varchar string comparison is working here?

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Transact SQL :: Dynamic Partition For Partitioning Table

Jul 31, 2015

I am new to Partitioning tables. My scenario is as listed below.

I am getting Monthly Transaction data on Every First Monday of the Month and I want to do partition for those data.

For Example: Let's say I will get my next monthly data on August 3rd 2015 which is First Monday of the month of August.

I want those Transaction data to go in new partitioned FileGroup in my existing partitioned table. How can I do partition for this kind of scenario ? Can we create one or multiple Stored Procedure which will create New Partition and load data in that partition ? 

FYI, this monthly data will be loaded in Staging table and that table has LoadDate column which will have 2015-08-03 in it.  I am using SQL 2012 Enterprise edition.

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Performance Based Transact Coding

Aug 28, 2006

Hi all,

I am looking for some study meaterial focussed on performance based transact SQL development. I am a fairly well seasoned (3+ years self taught), and I am getting into situations where different query constructs yield the same results, but the performance (execution time and disk I/O) varies.

I have found that sometimes nested select statements execute faster than joins, but usually the opposite is true, for example, and I would like to learn why.

Info would be appreciated.

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Transact SQL :: Performance Tuning On Triggers

Oct 12, 2015

I have table A and B. A has column ID,A1,A2,A3,A4,A5 columns. B has ID,B1,B2, A1 columns. A table has a trigger. I defined the below trigger. 

Solution 1
ALTER TRIGGER [dbo].[Tri_A]
ON [dbo].[A]
for UPDATE
AS
BEGIN
   UPDATE B
  SET  B.A1= i.A1
  FROM  inserted i
     INNER JOIN B 
      ON B.ID = i.ID
END;
GO

If I change the above solution 1 trigger to solution 2.Can I improve the trigger performance dramatically? I mean only A.A1 is changed then update B.A1. So when the other columns is changed, the update will not be required.

Solution 2
ALTER TRIGGER [dbo].[Tri_A]
ON [dbo].[A]
for UPDATE
AS
BEGIN
IF ( UPDATE (A1) )
   UPDATE B
  SET  B.A1= i.A1
  FROM  inserted i
     INNER JOIN B 
      ON B.ID = i.ID
END;
GO

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Transact SQL :: Altering A Table Without Impacting The Performance?

Sep 15, 2015

Altering a table which is having more than 100 million rows. Would like to know the best possible way to add a new column to this table without impacting the performance much.

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Transact SQL :: Huge Performance Difference For Same Select Between Environments

Jun 22, 2015

I have encountered a problem with a specific set of tables. The same select yields slightly differing execution plans in two different environments (instances). But the slight variation seems to contain a huge differences in stats. I don't know the significance of these stats. The two tables have the exact same indices.

This is the selcet statement:

SELECT 'xx' FROM DUKS.dbo.Profiler
WHERE DNA_Løbenummer IN
(SELECT DNA_Løbenummer FROM DUKS.dbo.Effektregister
WHERE Sagsnummer = '2015-00002')

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Raw Partitions

Jan 9, 2002

Does anyone have any statistics on the performance gains one can get using raw partitions. The database in question is very IO intensive and performs about 1,000,000 inserts/updates per select.

Thanks...

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SQL Installed On Both Partitions

Oct 12, 1999

Please help!

I have a server that has SQL Server installed on both C and D drives. The SQL Server software is currently running from the C drive and the live databases and backups are stored on the D drive.

I need to have everything on the D drive. Is there an easy way to make the registry point to the D drive without reinstalling SQL Server? The software will needs to run from the D drive because the C drive is running out of disk space. I will also need to delete the whole C:mssql directory.

Thanks.

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Moving Partitions From One DB To Another

Jun 19, 2008

assuming that you have two databases, the OLTP db and the OLAP db (take not that both have the same structure -- archiving purposes)... using table partitioning, is there a way where we can move 1 partition from the OLTP db to the OLAP db???

i'm actually trying to use this example with both tables in the DB.. I tried to modify to use two databases but sql server is unable to move the partition...

ALTER TABLE [Production].[TransactionHistory]
SWITCH PARTITION 1
TO [Production].[TransactionHistoryArchive] PARTITION 2;

SlayerS_`BoxeR` + [ReD]NaDa

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Configurations For Partitions.

Aug 23, 2007

Hi experts,

In SQL Server 2005 database we have partitioned a very big table into 30 partitions each holding few million of records.

Im just curious to know whether there are some configuration related to processors or system hardware in order to benefit from partitioning ? (Ex : If we have multiple processors Whether they need be configured to do a parallel processing ? )

Any real time experience (other than referring links) would be really helpful for me.

Thanks in advance,

Hariarul

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Merging Partitions

May 21, 2008



Hi There,

I have a quick question regarding merging cube partitions.
If I create partitions sliced by date (let's assume we have year level partitions like 2006,2007,2008...)
Later, if I want to merge selected partition to another partition , for example I have history partition and 2006 partition and I want to merge 2006 to history partition then I can simply merge them using ' merge partition' through Management Studio.

My question is that in script, History partition has condition which is where clause and restricted by year level (i.g. WHERE date < '01-01-2006' ) ; however after merging , script won't change like WHERE date <'01-01-2007').

If so, whenever I merge partitions then I have to alter the script as well based on selected merge partion?
I need to refresh history partition once a month;however even if I merge 2006 partition , once I reprocess history partition then it only process what it was wrote in script. So, after reprocessing 2006 data won't appear in this history partition.
So, wondering it's mentatory to alter the script once partition is merged.
Please give me some comments on this issue.
Thanks in advance.

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Horizontal Partitions - Not Working As Described

Apr 16, 2002

I am testing horizontal partitions to see whether it is a feasible
option for a project. IF I have a composite Primary Key and the
constraint column (a part of the Primary Key) that helps the
partitioned view is defined with DateTime Data Type, select on a restricted set of data through a partitioned view still tries to access all the tables instead of just one table that contains the data. Is this the case or am I
missing something ?

Any help on this is appreciated.


Here is what I am trying to do.

************************************************** **************

CREATE TABLE [dbo].[tst01] (
[Dt] datetime NOT NULL ,
[TID] int NOT NULL ,
[Nm] [char] (10) COLLATE SQL_Latin1_General_CP1_CI_AS NOT NULL
) ON [PRIMARY]
GO

CREATE TABLE [dbo].[tst02] (
[Dt] datetime NOT NULL ,
[TID] int NOT NULL,
[Nm] [char] (10) COLLATE SQL_Latin1_General_CP1_CI_AS NOT NULL
) ON [PRIMARY]
GO

ALTER TABLE [dbo].[tst01] ADD
CONSTRAINT [PK_tst01] PRIMARY KEY CLUSTERED
(
[Dt], [TID]
) ON [PRIMARY]
GO

ALTER TABLE [dbo].[tst02] ADD
CONSTRAINT [PK_tst02] PRIMARY KEY CLUSTERED
(
[Dt], [TID]
) ON [PRIMARY]
GO

ALTER TABLE [dbo].[tst01] ADD
CONSTRAINT [CK_tst01] CHECK (Dt between '11/1/2002' and '11/30/2002')
GO

ALTER TABLE [dbo].[tst02] ADD
CONSTRAINT [CK_tst02] CHECK (Dt between '12/1/2002' and '12/31/2002')
GO


insert into tst01 values('11/1/2002', 1, 'SS')
insert into tst01 values('11/2/2002', 2, 'KK')
insert into tst01 values('11/3/2002', 3, 'DD')
Go

insert into tst02 values('12/1/2002', 1, 'LL')
insert into tst02 values('12/2/2002', 2, 'MM')
insert into tst02 values('12/3/2002', 3, 'GG')
Go


CREATE VIEW vtst AS
SELECT * FROM tst01
UNION ALL
SELECT * FROM tst02
Go

SELECT * FROM vtst WHERE dt = '11/1/2002'

************************************************** *********

When I look at the Execution Plan, it shows that clustered index seek
would be performed on both the tables.


StmtText
---------------------------------------------------------------------------------------------------------------------------------
|--Concatenation
|--Filter(WHERE:(STARTUP EXPR(Convert([@1])<='Nov 30 2002
12:00AM' AND Convert([@1])>='Nov 1 2002 12:00AM')))
| |--Clustered Index
Seek(OBJECT:([test].[dbo].[tst01].[PK_tst01]),
SEEK:([tst01].[Dt]=Convert([@1])) ORDERED FORWARD)
|--Filter(WHERE:(STARTUP EXPR(Convert([@1])<='Dec 31 2002
12:00AM' AND Convert([@1])>='Dec 1 2002 12:00AM')))
|--Clustered Index
Seek(OBJECT:([test].[dbo].[tst02].[PK_tst02]),
SEEK:([tst02].[Dt]=Convert([@1])) ORDERED FORWARD)


Thanks,
Sathish

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Update Horizontal Partitions

Feb 24, 2004

I'm considering using horizontal partitions to separate my data by year.
For example, SomeTable_2004, SomeTable_2003, etc. This works well for backups, maintenance, etc. because I'm working with 150+ GB of data. I'll be a partitioned view for queries.

However, I'm new at this and have a few questions. I would also like to do partitioned updates or inserts. But I need to make sure that the tables don't use similar primary keys. Does that make sense? I need to make sure that the primary keys from the first table are not used again in the second table.

SomeTable_2003
primary keys: 1,5,8,9,15

SomeTable_2004
primary keys: 2,3,4,10

I don't really care what keys are used on what table, as long as they are different. I have apps that already use this data, and I don't want to change the application logic.

Thanks,
T

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SQL Server 2014 :: How To Set Up The Partitions

Oct 1, 2015

how to set up the partitions.I have a transaction table with 50 million records that's very hard to query. it holds data for the last 4 years but the application only ever looks at the last 6 months so i believe this is and ideal candidate for partitioning.

Would it be better to

1) create a partition based on each year for all data so would have a 2015, 2014, 2013, 2012?
2) create 1 partition based on month for this years data then 3 based on year so would have jan,feb,march,april,may..., 2014, 2013, 2012

For 1) would you have to perform some maintenance at the turn of each year for accommodating the next years data. For 2) although this would give better performance as query's are mostly in the last 6 months wouldn't this have more maintenance to move month data to year partitions come the turn of the year and then create the next years months partitions.

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Physical Disk Partitions

May 21, 2007

I just inherited a dev box, and need to do some performance analyzing on a 40 gig db for a client. Time is of the essence!

My question is that this dev box only has one disk partition (c: drive). Is it a huge deal that I don't have the db system files on one drive, with the data files on another, and tempdb on another,etc.....

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Table Partitions & RAID 5.

Aug 28, 2007

Hi experts,

We have a huge table with around 250 million records and have implemented SQL server 2005's new table partitioning feature. Now the data seems to be evenly spread across 20 different filegroups ( each 5 GB approx ) for the same table that was occupying 100 GB itself in the PRIMARY filegroup earlier.

Still the query response times have not come down drastically but we could see a good improvement in the execution plans now.

WE ARE USING RAID 5 IN OUR PRODUCTION ENVIRONMENT. ANY IDEA / THOUGHT ON HOW TO PLACE THE PARTITIONED FILEGROUPS AND THE LOG FILES IN THE RAID 5 (BTW , I'm very new to RAID concepts , any detailed instruction would be helpful ).

Any help would be greatly appreciated.

Thanks,

Hariarul

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Data Moving Between Partitions

Mar 9, 2008

I have a requirement that I need to reload the last seven days worth of data each night to ensure that we pick up late arriving and updated records. To avoid having to do updates we delete the last seven days data and reload.

I was wondering if it is possible to set up the table as a partition, paritioned on a value (OLD, NEW) or similar.

The job would set the last day in the NEW partition to be old, the theory being that this would cause the rows to move to the OLD parition, and then truncate the new partion rather than deleting. The last seven days data could then be inserted into the empty new partition.

My questions is 1. Is my theory about the data moving from one partition to another correct. 2. Can I actually truncate and individual parition, 3. Do you think it will perform any quicker. We would expect data in the range of 100K to 500K rows in the seven days and will store up to 4 years of historical data.

Thanks for your thoughts

Stapsey

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Better Table Management (partitions?)

Oct 31, 2006

Hi,

For my work I am now learning Sql server 2005 and I have been given a database that has been set up by someone else to work with. It is my job to get the database ready for use in reports.

My problem is that the current database has one huge table with almost 8GB of data. The table contains data from 2004 to present (and growing) from 14 different countries. The reports we use are mostly per country, but we also want to compare the 14 countries to eachother for say, whole 2006.  At the moment the table is stored in one single file instead of using partitions.

I believe partitions can give a good performance boost when running the queries. But how do I do this? Currently the country codes are just plain text, can they be used for partitions?

Any advice would be welcome,

Thanks!

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Summarize Data Over Partitions

Oct 17, 2007

Hi champs!
The data i have is like this:

nr date value

------- -------------- --------
1 2007-10-03 45
1 2007-10-05 5
1 2007-10-11 -1
1 2007-10-30 23
2 2007-03-03 3
2 2007-03-13 -5
2 2007-03-03 6
3 2007-10-03 42
3 2007-10-03 11

.....

I want to summerize the value in each group and set the date to the 1'st og that month
i.e.
nr date value

------- -------------- --------
1 2007-10-01 72
2 2007-03-01 4
3 2007-10-01 53


any help is much appreciated.
thanks

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Moving Indexes To Seperate Partitions

Jul 8, 1999

I have been asked to move the indexes on our membership database tables to seperate partitions on the server. This is a new concept to me and thought I could use some advice on how to go about doing it.

Thanks in advance.

Brad Keck

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SOS - Table Partitions Or Indexed Views.

Feb 26, 2008

Hi Experts,

We have a very huge database that stores 12 years of data(120 Million records). But our application mainly accesses past 3 years data i.e , the queries would scan the 120 million records even when it actually has to scan 30 million records alone (for 3 years).

Since few other important applications needs access to all the 12 years data, we are in a position to have 12 years data in the same database.

Right now we are looking for an approach that would help us to efficiently access the 3 years data alone and boost the performance.

1. Will SQL server table paritioning help in this scenario ?

Or

2. Indexed views would help us ? Is it possible to create indexed views based on year range and access the views in the stored procedures ?

Any help would be greatly appreciated.

Thanks in advance,

Hariarul

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Analysis :: Aggregation Design - Using Partitions

Jul 31, 2015

I have 3 partitions using a year grouping. Current year, previous 4 years, older than 5 years. I have two measure groups, one is a distinct count, so I actually have 6 partitions.I also use usage based optimization to build my aggregations. Should each partition have a separate aggregation or should there be one for each measure group?

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Overlapping Partitions And Join Filters

Oct 2, 2006

I am using Sql 2005 and merge replication with push subscriptions. I have several dynamic join filters on some of my tables.

The join filters all use a central table that maps say a server location name (something that is returned from HOTNAME() in my case) to an for a store branch ID. This is a retail system database.

When I add a new new subscription I update this table with the new server location name and it's corresponding branch ID. My filtered tables all have a foreign key in them that is the branch ID. I can then effectively join from the server location name to a Branch ID.

What I have noticed is that if I update one row in the map table, sql server will re-generate all partitioned rows for all subscribers, even for rows that haven't been updated.

The net result is that when I add a subscription, my existing subscriptions all get about 52,000 row updates.

Am I seeing this because I said my partitions will overlap when I created the table articles?

Thanks for any help

Graham

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Can Data Partitions Be Used With Associative Tables?

Aug 1, 2006

First of all, we are using SQL Server 2005 with a SQL Mobile subscriber and we are attempting to use Data Partitions on our current database
schema which contains associative tables for many-to-many relationships.

We have two tables, a User table
and an Audit table. A user can be
assigned more than one Audit. An Audit
can be assigned to more than one User.
So an AuditUser associative table exists. If data partitions are used based on User,
then any Audits that are assigned to one or more users should be copied to the
proper partition for each User (the msmerge_current_partition_mappings table
with the proper partition_id values).



In order to insert records with such a schema, the following
steps occur in order:

Insert
new row into Audit table with new rowguidInsert
entry into AuditUser table associating the auditguid with every userguid that
is assigned this audit.



Merge replication triggers are fired on insert of the Audit
row and another one for the insert of the AuditUser row.



When the Audit row is inserted, the replication trigger follows
the following logic:

Inserts
a copy of that row into the msmerge_contents table. Evaluates
the row to determine which partition(s) this row should be copied to as
well (msmerge_current_partition_mappings table). To do this, it checks to see if the
AuditGuid is referenced in one or more AuditUser rows. Since we haven€™t inserted the AuditUser
row at this point, the trigger€™s logic doesn€™t find a partition to copy
this row to.



When the AuditUser row is inserted, the replication trigger performs
the same logic as with the Audit row, it:

Inserts
a copy of that row into the msmerge_contents table.Evaluates
the row to determine which partition(s) this row should be copied to as
well (msmerge_current_partition_mappings table). Since the row meets the criteria for one
or more partitions, it is copied to the msmerge_current_partition_mappings
table for each partition that exists.



When replication occurs, we see only the AuditUser rows
copied down to our device, and not the corresponding Audit rows. Now that we understand the triggers, it is
plain to see why. If the AuditUser row
could be inserted first, then the trigger on the Audit row would copy that row
into the proper partitions and all would work well. However, the Audit row must be inserted
first, so that foreign key relationship constraints are preserved.



It seems that the Update trigger on the AuditUser row
actually walks the relationships and copies any related child rows to the
msmerge_current_partition_mappings table.

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SQL Server 2005 Partitions And SAN Array

Jul 3, 2007


I am looking for information/suggestions in regards to portioning data across a large SAN. The database is several TB in size, and we are looking to partition the data on a date so that the current data is always the fastest available and history can be set as read only but still be available.

If the server has 8 drive letters how can I ensure that the 4 data drives are stripped across the most physical drives for the most through-put??

Are there any specific questions I need to ask the server technicians?

Any pitfalls I should be aware off??

Thanks!!!

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Dynamically Add Partitions To A SSAS Cube

May 9, 2007

The environment here is SSIS ETL feeding a Fact Table. The Fact Table is pulled into SSAS as a cube and reporting services are handled there. I am on the ETL side and don't pretend to know all the processing that happens with cubes, etc.



What we are trying to accomplish is to add partitions to a Cube via the ETL processing. The partitions should be incremented by Day, i.e. 20070501, 20070502, etc.



This is currently processed manually by the Reporting developer and we are looking for an automated process to reduce errors and hand work.



I have explored the following objects: Partition Processing DataFlow Destination and did not find much documentation or examples on it's use. If you have any information on this stage, please reply with such.



The other option is the Analysis Services Processing Control Flow. I understand that we can process Analysis Server objects as part of our package. Is there a way to incorporate a Partitioning Script in this object? If so, how. Again, I did not find detailed examples on the use of this object.



If you have experience with either of these, please feel free to reply. I appreciate any and all comments.

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How To Create Partitions On Cube Using SSIS?

May 5, 2008



Hi,

I am currently using SSIS ,MS Sql Server 2000 database and 2000 Analysis Services for the cube.
I am creating a new table everyday and giving name like day_20080504, day_20080505 etc...
So then I go to Analysis Services and process dimensions(incremental) AND
Create a new partition using old partition as a template.

My first question is how to create a new partition everday and use old partition as template...(Almost same except database table)
My Second question : Can I do this on 2000 Analysis services or Should I convert my cube into SSAS?

thanks,
J

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Why Does Moving Data Between Partitions Take So Long ?

Oct 17, 2007

I have a table with millions of rows and about 70 columns that move through a number of states (11 possible states in all) from "New" via various states to "Processed" and eventually to "Archive" (there's a complicated state diagram that I won't bore you with)


Movement between states is based on a heap of business logic including the move to Archive (not just dates).


Different sorts of processing (querying and update both by users and overnight processing) are carried out on the data according to its state.


Maintaining the indexes for optimum performance across the board is a headache.


We have two problems in that we want better query performance and want to be able to easily switch out objects that are in the Archive state.


I had in mind partitioning the table (and its indexes) on state so that :
(a) Queries would be directed only at the appropriate partition (that is always use "where state=" as part of the query)
(b) The Archive partition could be swapped out of the table periodically


In my test setup 10 of 11 partitions are in [PRIMARY] but Archive is in a different filegroup.


Query performance is OK - execution plans look good.


However my update performance is now appalling when moving between any two states (10 times as long as on the unpartitioned table).


I understand that when you update a column which is used as a partition key it will cause the row to "move from one partition to another" as it says in another post.


Fine - because that's exactly what I want - logically.


I can also understand that moving from one filegroup (and hence the underlying file) to another must mean that the data has to physically move.


However is the data physically moving whenever you move between partitions or what's going on to cause such a degradation in performance ?

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Table Partitions On Existing Tables.

Jun 4, 2007

Hi guys , assuming right now I already create partition function (PF_Date) and partition scheme (PS_Date). Let say I would like to implement the partition on the existing tables ( eg: transaction table which is in PRIMARY filegroup), how am I switch it from PRIMARY to PS_Date ? Is it I have to re-create the particular table then only able to put in the partition scheme? Hope can get any assistance here. Thanks alot.



Best Regards,

Hans

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