So we have new servers that are going to be installed with SQL 2012 and I'm debating the wisdom of splitting tempdb with multiple files.
I know it's a myth that performance automatically improves if you split it into a number of files based on processors, but I'm debating the wisdom of putting a file on each of my data / log file drives.
For instance, I have a server with a C: drive (OS), D: drive (Data for system DBs and install of programs - 458 GB), an F: drive for user DB data files (767 GB), and a J: drive for log files (255 GB).
Obviously no files are going on C:. I'm debating on whether or not we should even leave system DBs on the D: drive given in our current 2k8 servers, we end up with Memory.dmp files over flowing the D: drives as well as .cabs and other install / update files that tend to collect on that drive over the years.
But if we leave the system DBs on D:, I'm wondering if adding a second tempdb file to F: and a third to J: will improve query performance or not.
I'm quite new to SQL. I'm able to extract the info that I need, but only into a result of one row, like:
Order header | Order details
ID | Customer name | Customer address | Product number | Product name | Quantity | Price | Product number | Product name | Quantity | Price 2 Andy Andy's way 2 24 Glue 3 35 39 Oyster 2 9
Looking for returning multiple entries from a time span. I have a date, start-time, end-time and duration. I need the start-times separated in a list. It's fine if temp tables are needed - I have that clearance.
I have a description field in a table which also stores unit of measure in the same column but with some space between them, I need to split these into two different columns.
I'm having an argument with our infrastructure architect who has just gone and bought lots of SSD drives to use for our tempdb data and log files, sounds great doesn't it? There is a catch though, his plan is to add the disks to the two available slots in each blade in a RAID0+1 configuration, effectively giving you one usable drive, and adding both data and log files on to one disk.
I then pointed out that SQL Server best practice is to host tempdb data and log files on two separate drive to reduce contention. The architect then basically said that because this isn't spinning disk the issue of drive, r/w contention isn't an issue I don't agree with this and wanted to get some opinions from the community, I'm still advising that two separate disks should be used but someone just went and spent £80k ($150k) on SSDs and doesn't want to back down...
I have a tempdb split into 4 files (5 if you include the log).
Autogrowth is disabled on the mdf/ndf files so that they can be used round robin (1 file per logical CPU).
Is there a way to be alerted when there is x% of free space left?
I know hwo to check the free space via t-sql but want to be able to be alerted. I could run a sql job that reports the free space and send a database mail message if under x% but wondered if there was a built in (or better) method?
I was in the process of creating additional TempDB.ndf files, and received an error saying they already exist. I checked the location and it was empty, nothing to see here. So I looked in sys.master_files and there are several tempdb files listed in various locations, all of which come up empty.
So the files are listed as online in sys.master_files, but they do not exist on the server. I restarted SQL services but it did not change anything.
I am currently investigating aa high avg write time ms issue (145ms) which seems to be only occuring on the tempdb data files.I have followed the recommended setup of TEMPDB in that
1. Data files = number of physical cores 2. Data files and logfiles are on separate partitions away from the other databases. 3. Tempdb is presized and no incremental file increases look like they are happening with frequency.
We have sharepoint 2012 setup on other sql servers and with TEMPDB setup following the same guidelines, with far more Sharepoint activity on a similary specified hardware which is why its confusing.FileIO auditing on the partitions themselves shows that the FileIO is very fast on the partitions that the tempdb data file which leads me to beleive that Sharepoint may be the culprit perhaps due to excess use of tempdb with operations taking a long time to resolve.
I proposed on a new server that we separate Data Files, Log Files, tempDB, Backups, etc. onto separate LUNS on a SAN with High Speed Solid State Drives.I was told that with the new technology with solid state SAN's that it would decrease performance and that it did not work the same way as it did when you had RAID 5's etc.I thought that if things were cared out correctly by a SAN Administrator they would know how to configure for optimal performance.
I had a query regarding splitting MDF files. As one of our databases has an mdf sized 75GB, I was planning to split it into 2 or 3 files and put them across different RAID disks. But I could not find a thorough source for information as to how to go about splitting an existing MDF file into smaller files. Can anybody help?
I am testing out a blank database created over two physical files on two separate disks with one table called data which has one column called values nvarchar(max).
I filled the table up with a whole load of data and ran a select * against it. If I run Permon at the same time I can see that the read load has been spread over multiple disks as each of these disks is getting read from in parallel. If I create the same database on a single file and run the same select * again it takes much longer, proving that the read load has been distributed across multiple disks.
Now moving onto writes, this is where the confusion lies. I understand that SQL server fills files evenly until they need growing, after which it will then fill files individually until they are full in a round robin fashion unless you have trace 1117 turned on. What I don't understand is why the writes aren't distributed out whilst it is filling these file groups.
I ran an continual insert into my table with go 1000000 to monitor how the files are being filled up. I monitored where SQL server was physically placing the files as they were being inserted by running the following query:
;WITH CTE AS (SELECT sys.fn_PhysLocFormatter (%%physloc%%) col1, RIGHT(LEFT(sys.fn_PhysLocFormatter (%%physloc%%),2),1) AS [Physical RID], DATAID
[Code] ....
I could see that it would a thousand or so records into file 1, then a thousand or so into file 2, then a thousand or so into file 1 etc etc. In another words it would hit one disk, then another disk, then back to disk one to fill the file evenly. Is there any way to make SQL Server distribute the writes out in parallel so that both disks are writing in tandem?
By the looks of it, multiple disks only scale reads, as with writes only one disk is ever written to at once which is annoying. Any way to harness the write power of multiple disks?
I have to split a column using comma a delimiter into multiple columns. I am able to do it if i know how many column will be present in the final output. But in daily run, the columns may vary randomly.
how to split columns without hardcoding how many columns it ll come.
This is the code am using
Code: WITH Split_Names (Fil_id,Name, xmlname) AS ( SELECT Fil_ID,
all the columns are separated with a "|" but the amount of columns are not fixed, so in lines 1 & 2 they are 4 columns and in line 3 there is 7 columns
I'm creating a web-based NT RAS report site and am looking for the most efficient way to import the data from NT Event log into SQL2k. I'm using the 'dumpel' utility from rsc kit and all is fine except the 10th column - the message detail:
"The user DOMAINuserid connected on port Mdm15 on 08/23/2002 at 07:25am and disconnected on 08/23/2002 at 07:27am. The user was active for 2 minutes 23 seconds. 78809 bytes were sent and 50675 bytes were received. The port speed was 49300."
I need to parse this one long text string into 6 distinct columns: userID, port, duration, bytes_xmt, bytes_rcv and portspeed. After a quick review of the rowsets, the strings seem to hold a consistent output ... no real variances I can see.
I've dablled with views but am facing a small performance issue that could get bigger: The sql server not only has to run the text file import package, but also the view to format the text dump into a workable dataset, then my report code bangs over 30 queries against the final dataset. It already takes our SQL2k server over 3 minutes to parse about 20,000 rows and the server's a beast (dual 1.8 p4 cpu, 3gb ram, raid, etc).
What I think would work best is to abandon the view (performance will only get worse as the row count increases) and instead INSERT the rows into one table.
Any ideas anyone? any good scripts out there that can help me to parse the long text string quicker that using substring and replace functions?
I have a large poorly designed table (inherited) With a Name field that contains comma delimited text containing address information. I need to do several things with it but unfortunately there doesn't appear to be any true consistency in it. When it displays in its own text box it works by placing each section on a new Line and looks ok.But I need to pull it apart and place things like unit number, Building Name in its own column etc. In the data it could be in either the 2nd,3rd, 4th, dependent on what came 1st. the data looks some thing like the following
unitNumber/StreetNumber Space StreetName (Building Name), Subub,City,Country
Some addresses won't have unit number or Suburb or country so when splitting you could have Suburbs and Citys in multiple columns even if you try and stagger the split process.Has any body go a good tool or reference site for dealing for this sort of problem. I have a table that I have made up that has some of the street names that could be used for comparing against existing records but it is by no means fool proof due to spelling inconsistencies . I also have another list of Common building names that could be used to compare, remove and place in the new building column.
What I need is split the data into two columns if data in column Main starts with 'PR-' then output result to column P and if it starts with 'CC-' then to column C (the output needs to be in one table).
Hi i want to create a table as follows :if exists (select * from dbo.sysobjects where id =object_id(N'[Indexes]') and OBJECTPROPERTY(id, N'IsUserTable') = 1)drop table [Indexes]GOCreate table Indexes(indexname Varchar(100), index_DescriptionVarchar(100), index_keys Varchar(100))GOINSERT INTO Indexes EXEC sp_helpindex 'SDM_Fact_Order_Detail'GOThis will give me a table (northwind)IX_Auto_SDM_Fact_FK_Shipped_Date nonclustered located onSAMIS_SDM_Index FK_Shipped_DateIX_Auto_SDM_Fact_Order_Detail_FK_Insert_Dateclustered located onSAMIS_SDM_Data1FK_Insert_Date, FK_Insert_TimeAs you see sp_helpindex will give me a comma seperated field. I wantto split the third column FK_Insert_Date, FK_Insert_Time into a extrarowLike this :IX_Auto_SDM_Fact_FK_Shipped_Date FK_Shipped_DateIX_Auto_SDM_Fact_Order_Detail_FK_Insert_Date FK_Insert_DateIX_Auto_SDM_Fact_Order_Detail_FK_Insert_Date FK_Insert_TimeCan anyone help me with this?ThanxHennie
SUBSTRING(@s, start, CASE WHEN stop > 0 THEN stop-start ELSE 512 END) AS s
FROM Pieces
)
This works very well, other than instances of the delimter are, themselves, considered to be results. For example:
SELECT * FROM vs_SplitTags(' ', 'foo bar') AS result returns: pn s 1 foo 2 bar
which is exactly the result I would want.
However, SELECT * FROM vs_SplitTags(' ', ' foo bar ') AS result -- There are spaces before 'foo' and after 'bar' returns pn s 1 2 foo 3 bar 4
And SELECT * FROM vs_SplitTags(' ', 'foo bar') AS result -- There are two spaces between 'foo' and 'bar' returns pn s 1 foo 2 3 4 bar
I want the function to ignore whitespace altogether, be it a single space or multiple spaces. Other than to delimit the boundries between words, of course.
In other words, all three examples above should produce the same result: pn s 1 foo 2 bar
How can I do this? Any thoughts much appreciated...
I have a very interesting problem in T-SQL coding for which I can't figure out the solution. Actually there is a Line_1_Address column in our data warehouse address table which is being populated from various sources. Some sources have already concatenated house number + street address fields in the Line_1_Address column whereas one source has separated columns for both data fields.
Now I'm trying to extract data from this data warehouse table and I need to split the house number from street address and load it into separate columns in my destination table. In case there is no data for house number then I should load it as NULL.
The issue is that data in this Line_1_Address column is very inconsistent so I don't know which functions to use. Here is some sample data for your consideration:
Line_1_Address 101 E Commerce ST 120 E Commerce ST 2 Po Box 301 W. Bel Air Ave West Main Street, PO Box 1388
Currently I have a column with multiple postcodes in one value which are split with the “/” character along with the corresponding location data. What I need to do is split these postcode values into separate rows while keeping their corresponding location data.
Why shrinkfile empty file does not redistribute data evenly in the primary file group with multiple files:
Please run the script attached to see what the end result is.
This is what I set up last night on my test machine.
1) Create database [FGTest] size 200MB 2) Create table called TEST on primary 3) Insert 40MB of data into test 4) Create another file group called temp in primary size 200MB 5) Shrinkfile('FGTest',emptyfile) so that all data is transfered from FGTest into temp file group. 6) Add another 2 files called DATA2 and DATA3. Both are 200MB. 7) We now have 3 empty files that I want data distributed evenly on. FGTest, DATA2 & DATA3 8) Shrinkfile('temp',emptyfile) to move all the data from temp over the 3 file groups evenly
I would expect at this stage to have the following:
FGTest = 13MB, DATA2 = 13MB, DATA3 = 13MB
(40MB of data over 3 files should be about 13 MBish in each file)
What I actually end up with is this:
FGTest = 20MB DATA1 = 10MB DATA2 = 10MB
It looks as though SQL Server is allocating 50% of all data to the original file and then 50% evenly over the remaining files in PRIMARY.
I was in the process of migrating a server from one physical box to another. They are identical drive setups, same OS (2003), same SQL install (2005). Our server team did a 'PlateSpin', which copies the drives from one server to another, as long as the files are not in use. I did not reinstall SQL on the new box, i let the 'PlateSpin' tool copy everything over for me. I then stopped the SQL services on the old server and new server and copied over all of the system database (.mdf & .ldf) files. As soon as i started up the services on the new server, it looked great with one exception. The TempDB was only showing one datafile. When i queried sys.master_files, it was showing me 8 TempDB files. I tried restarting the services, but i still saw the same, only 1 file. I then tried to re-add TempDB files with the same name, but it would error saying they already existed. In turn, i could add new files with different names and they showed up fine. However, on a restart, they would not show up in the properties of the TempDB.
When i queried, sys.master_files again, i now had 16 Temp db files listed in the results. I deleted all but the original single file that was recognized out of the sys.master_files table and re-added the additional 7 files with he original names, restarted the service and then they all appeared.
Hi all, I have a tempdb that consists of 8 datafiles, tempdb_data_1 totempdb_data_8, each is 8GB. Now how can I drop 7 of them and leaveonly tempdb_data_1? Can this be done? Thanks a lot.
Documentation that supports the placement of Tempdb files on the root of a drive, i.e T: instead of T: empdb. I am positive this is not a best practice, but when challenged could not find any documentation that would support that view.
It's been a long time since I've tried this, but I have a SQL Server that needs to be restored (including master) to a server whose drives and corresponding folders match the source server, with the exception of tempdb. When SQL Server initially starts I believe it will fail since it cannot find tempdb. I just don't recall if it fails to startup or if it starts up reporting errors and recreates tempdb in the same location as master. Does anyone recall the steps needed to point SQL Server to the new location of tempdb?
We had someone create an extra data file and log file for tempdb. Sowe currently have two data files and two log files. Is it possible todelete the newly created data and log files? If I just delete thephysical files, I assume they'll get created as soon as SQL Servergets started back up. Any help would be great, since a single dataand log file for tempdb is my goal.Thanks much.sean
Have a SQL2008R2 instance on a VM where the single .mdf for the tempDb database is located on a high contention disk. I've managed to get another 60GB disk and thought it would be a good time to move the .mdf and also increase it's size and number of files.
The server has 12 cores and after a bit of reading I've decided that it would be best just to have four files for this database as the 1 file per core (-1) seems to be disputed.
-- Move the existing file to the new disk and rename it. ALTER DATABASE tempdb MODIFY FILE (NAME='tempdev', FILENAME='E:SQLData empdb0.mdf');
-- Change the size to 1GB ALTER DATABASE tempdb MODIFY FILE (NAME='tempdev', SIZE= 1048576KB, FILEGROWTH=5%);
-- Add three new files, all with the same size & growth ALTER DATABASE [tempdb] ADD FILE ( NAME = N'tempdev1', FILENAME = N'E:SQLData empdb1.mdf' , SIZE = 1048576KB , FILEGROWTH = 5%) ALTER DATABASE [tempdb] ADD FILE ( NAME = N'tempdev2', FILENAME = N'E:SQLData empdb2.mdf' , SIZE = 1048576KB , FILEGROWTH = 5%) ALTER DATABASE [tempdb] ADD FILE ( NAME = N'tempdev3', FILENAME = N'E:SQLData empdb3.mdf' , SIZE = 1048576KB , FILEGROWTH = 5%)
-- Now restart the instance.
Also, what are peoples thoughts on percentage growth for tempDb? I've read that it's not recommend and yet it seems to be the norm.
Just found that my tempdb is always full whenever I run a query against a large database. Could please any experts here give me any advices on what is tempdb database used for and how to determine what files can be deleted from it?
I am looking forward to hearing from you and thanks a lot in advance.
