SQL Server 2008 :: Relation Between Max Degree Of Parallelism And Number Of CPU Cores
Jun 12, 2015
I have got a question on max degree of parallelism and CPU cores.
If max degree of parallelism = 1, this signifies that sql will use serial execution plan (unless u change it in query level with MAXDOP hint). In serial plan, will the query use all CPU cores (say in my server I have 16 core processors)?
If in serial execution plan only one thread works, then what the other threads doing ? Idle (I may have a defined max server worker thread = 32767(by default)
Unable to create a relationship between this parameters.
hi,i've set 'max degree of parallelism' to 1 because some sql request hanged.Now when i connect, how can i set the parallelism to 4 for a session.Is there a command like this :'alter session set max degree of parallelism 4' ?ThanksPaul
Microsoft SQL Server 2008 R2 (SP2) - 10.50.4000.0 (X64) Jun 28 2012 08:36:30 Copyright (c) Microsoft Corporation Express Edition with Advanced Services (64-bit) on Windows NT 6.1 <X64> (Build 7601: Service Pack 1) (Hypervisor)
This is just an UAT server which has OS and hardware detail below:-
OS :- Windows Server 2008 R2 Standard SP:- SP1 Processor :- Intel(R) Xeon(R) CPU X5650 @2.67GHz 2.66 GHz RAM : - 4 GB Bit - 64 bit
I want to set the value to max degree of parallelism, what value should i configure for the same?
Below is the snap property of SQL instance >> Processor
I have a server which is using total of 12 cores running an instance of SQL server. I was told to dedicate only 8 cores of CPU to be used by the instance for licensing purposes.
what the best way is to go about limiting CPU cores?
Referencing an article regarding MAXDOP and cost threshold for parallelism from Brent Ozar's website: [URL] .....
We have a 2 physical CPUs that are 4 cores each with hyper threading enabled. When looking through the task manager, under the performance tab, I see 16 CPU threads.We have set the MAXDOP value is set at 4.
Reading further, cost threshold for parallelism setting is recommended at 50 to start with.
Not sure where the culprit is for this error propping up. I've added a new measure group and Im trying to generate the schema for the resulting fact table, but something isn't right. However, I don't think its my new measure group that's causing the issue, because I removed it and still get this issue when I select Database > Generate Relational Schema
Hi, I want to put a Degree sign in a SQL server field. Can anyone tell me how to do this please (preferably on the data entry screen rather than by coding it in, as I need it freqently). Many thanks.
(idAuxiliarPF(BIGINT+PK), pf(BIGINT+FK), Data(DateTime), Descr(NVARCHAR))that has aprox. 50k rows.
I need to create a partition of the data to join to another table, the query that i have:
SELECT ROW_NUMBER() OVER (PARTITION BY pf ORDER BY Data DESC, idAuxiliarPF DESC) AS RN, pf, Data, Descr FROM dbo.PFAuxiliar WHERE Data <= GETDATE()This query takes around 40 seconds to return the results
If i remove the Descr column, the query it takes no time.
SELECT ROW_NUMBER() OVER (PARTITION BY pf ORDER BY Data DESC, idAuxiliarPF DESC) AS RN, pf, Data FROM dbo.PFAuxiliar WHERE Data <= GETDATE()I have two indexes, Clustered (idAuxiliarPF), NONClustered(pf).
I have client table which has client_id Eff_from and Eff_to columns.Eff_from and Eff_to are the dates that client is eligible for service. I need to know the average number of days from the day that he became not eligible and new eligibility date .
I have a new problem with doing a restore of a number of databases using powershell. The script I'm using is based mainly on this one (Part 2 in particular): [URL] .....
The problem I'm having is around the RedgateGetDatabaseName function. My hunch is that its down to the different version of red gate and how sqlbackup works. Basically when the call is made to the function it is returning both the Database Name and the number of row's that the SQL command in the function has ran. I've tried to include a SET NOCOUNT ON at the start of the SQL command in the function but its still returning the now count.
How to get the result similar to Ex2, instead of Ex1. (ie., case-number is in sequential order then no need to break), And it should suit large dataset, I will finetune, if any performance issue.
I have a table of Customers & their data in about 20 Columns.
I have another table that has potential Customers with 3 Columns.
I want to append the records from Table 2 onto Table 1 to the Columns with the same names.
I've thought of using UNION ALL or Select Insert but I'm mainly stuck on the most efficient way to do this.
There is also no related field that can be used to join the data as these Customers in table 2 have no Customer ID yet as they're only potential Customers.
Can I just append the 3 columns from Table 2 to the same 3 columns in table 1?
I am working now on optimization of an update query for a particular table and I want to measure the number of page splits after each update. How to check it?
We have a big software that run a warehouse distribution center, written in .NET Backhand is a SQL Server 2008 R2 STD database.
Now, it seems there is a problem with the sessions not being properly closed after each call to the DB. Here is the message got form SQL:
DESCRIPTION:A new connection was rejected because the maximum number of connections on session ID 57 has been reached. Close an existing connection on this session and retry.
In the .NET code, connection is made with the following code:
If oConn Is Nothing Then oConn = New SqlConnection If oConn.State = ConnectionState.Open Then oConn.Close() With oConn .ConnectionString = "Server=" & Server & ";Database=" & DB & ";User ID=" & User & ";Password=" & Pass & ";Connection Timeout=" & 5 & ";MultipleActiveResultSets=" & True .Open() End With
This code is called once, at the opening of the software
StoredProc are call with the code: Try oCmd = New SqlCommand With oCmd .Connection = oConn .CommandType = CommandType.StoredProcedure
[Code] .....
So every Command is closed after execution, yet, they stay active in the SQL Server. Is there something I'm missing here?
I have a table where I would like to update the document number row for 3k rows. The problem I have is that the documents come in sets of two (version 1 and 2) but both have different numbers. Picture it like this below:
DOCNUM: 4445787 Version 1 DOCNUM: 4445790 Version 2
It should be the same docnum (ie 4445787 Version 1, 4445787 Version 2).
The challenge is how can we assign the new docnum for version 1 to be also for version 2 as well. Basically in SQL we need a way to
1. Find a way to distinguish the pair of documents in the target db that are the same even though they have different docnums.
I'd like to get the column ID_NumofAttach to be populated by the total number of ID_Attachlevel column by the same ID_BegAttach or ID_EndAttach and populate where ID_Attachlevel is 0.
I need to create a script that adds an incrementing suffix to two columns, but restarts based on the value of another column. I found a similar question in the SQL Server 2000 forum, but it doesn't quite fit and also I'm working with SQL Server 2008 R2. The code below both creates a table with test data and tries to carry out the task. If you run this, you will see that the VISITNUM column has a value of UNS in row 4, UNS.1 in row 5 and UNS.2 in row 6. In row 7 it's V200, then in rows 8 and 9 it's UNS.3 for both. The same suffix gets applied to the VISIT column, but of course if I can solve this for VISITNUM then adding the suffix to VIST as well will be easy.
What I need is for row 8 to have UNS and row 9 to have UNS.1. In other words, any time the VISITNUM is UNS several times in a row, I need to add that ".X" suffix, but if a row has something other than UNS, I need to start over again the next time it's UNS again.
How can we monitor the all tables in all databases and send notifications to the team.Is there a way to check to find the no of rows and size of a table last month and find out growth % now
Our fiscal year starts on July 1st. Each month they call a period - so July is period 1, August is period 2, etc.
They are wanting a report that pulls numbers for a given period. There are parameters for them to select the fiscal year and the fiscal period, and then it calculates the numbers for that period. That part works fine.
Now they want me to do some calculations, and one of them is to divide one of the numbers by the # of days since the fiscal year. So if they choose July, it would be 31 days. If they choose August, it would be 61 days, etc. How can I set this up to calculate the number of days when they really aren't entering a start date, it's just a fiscal year and period.
Is there a way to calculate a date field that is 07/01/xxxx where xxxx is the fiscal year they chose? Also a way to calculate a date field that would be the last date of the month for the fiscal period and year they chose?
I suppose I could add 2 other parameters where they enter the start of the current fiscal year, and the last day of the period they're running it for, and use a datediff to calculate that. Just seems kind of redundant.
I have a challenge and I'm not sure the best route to go. Consider the following dataset.
I have a table of sales. The table has fields for customer number and date of sale. There are 1 - n records for a customer. What I want is a record per customer that has the customer number and the average number of months between purchases. For example, Customer 12345 has made 5 purchases.
We have a database. It is enabled for mirroring. We need to delete the old records. That is around 500k records from a table. But it has foreign key relation. How to do in Production servers these kind of deletes?
I'm trying to quantify the number of times folks use SQL Server Management Studio to change client data in one of our production databases. Does SQL Server keep this statistic? How do I get to this data?
Length specified in network packet payload did not match number of bytes read; the connection has been closed. Please contact the vendor of the client library. [CLIENT: xxx.xx.xxx.xx]
Client IP address is same as the server its producing the error on. I get these messages around 12pm everyday.
I have a single table that consist of 4 columns. Entity, ParamName, ParamsValue and ParamiValue. This table stores normalized Late Fee related parameters for apartments. The Entity field contains a code that identifies the apartment complex. The ParamName in a textual field that contains the name of the parameter that the other 2 fields define the value for; ParamsValue and ParamiValue. If the Late Fee parameter (as named in ParamName is something numerical then the value for that parameter can be found in ParamiValue else its in ParamsValue.
I don't know if 'Pivot' is the correct term to use for describing what I am trying to do because I've looked at the Pivot examples and I don't see how that will work for this. Using the Table and data as provided below, how would I construct a query so that I get 1 row per Entity in which the columns are the ParamsValue or ParamiValue for the ParamName listed in the column header (for the query)?
Below is the DDL to create the table and populate it.
USE [DBA_UTIL] CREATE TABLE [dbo].[PARAMEXAMPLE]( [Entity] [varchar](16) NULL,
