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SQL DBA – Stop multiple running SQL Jobs at once


 
Just like my previous post on Enable/Disable multiple SQL Jobs [link], here I will show how can we stop multiple jobs running by SQL Agent at once.

–> Although you can very well Stop a SQL Job in SSMS by simple right-clicking on it. But if you have multiple SQL Jobs running, to stop each of them will be a cumbersome and time taking task.

I will show how this can be done by a T-SQL query:

USE msdb;
GO

-- Stop Multiple running SQL Jobs at once:
DECLARE @dynSql NVARCHAR(MAX) = ''

SELECT @dynSql += N' msdb.dbo.sp_stop_job @job_name = ''' + j.name + N'''' 
			+ CHAR(10) + CHAR(13)
FROM msdb.dbo.sysjobs j
JOIN msdb.dbo.sysjobactivity AS ja 
ON ja.job_id = j.job_id
WHERE ja.start_execution_date IS NOT NULL
AND ja.stop_execution_date IS NULL
ORDER BY j.name;

PRINT @dynSql;
GO

Simply Copy-Paste the the above Dynamically generated SQL Script and Execute it, it will Stop all Running SQL Jobs at once.


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Categories: DBA Stuff, SQL Tips Tags:

SQL DBA – Quickly Clone a Database in SQL Server (2016 SP1 & 2014 SP2) with DBCC CLONEDATABASE command

December 22, 2016 1 comment

 
Have you ever been in a similar situation where your PROD database size is in GBs or TBs, and for a code-release validation or some performance-fix you need to restore it on an Dev or Test server? You know that taking backup & restore will take lot of time, but you have no other option.

We also face this many a times as our PROD database size ranges from 500 GB to 1-2 TB, and we end up waiting 4-5 hrs in this activity.

There are even third party tools, but they also take good time and have their own pros & cons.
 

Now SQL Server brings a new feature with SQL Server 2016 SP1 & 2014 SP2, i.e. DBCC CLONEDATABASE, to create a new database clone of an existing database within seconds. The new cloned database created is ReadOnly, with no data, but with Statistics.

With DBCC CLONEDATABASE feature you can generate a clone of a database in order to investigate a performance issue related to a Query or Workload.

Note: As best practice suggested by Microsoft product team this clone Database is not supposed to remain in PROD database, but can be moved to a Dev or Test box for further troubleshooting and diagnostic purposes.
 

–> Syntax:

DBCC CLONEDATABASE (source_db_name, target_clone_db_name)
[WITH [NO_STATISTICS][,NO_QUERYSTORE]]

 

–> The above statement creates Clone of the source database in following operations:

1. Validate the source database.

2. Get S lock for the source database.

3. Create snapshot of the source database.

4. Create an empty database by inheriting from “model” database, and using the same file layout as the source but with default file sizes as the “model” database.

5. Get X lock for the clone database.

6. Copies the system metadata from the source to the destination database.

7. Copies all schema for all objects from the source to the destination database.

8. Copies statistics for all indexes from the source to the destination database.

9. Release all DB locks.
 

–> Now let’s create a Clone Database on AdvantureWorks database:

-- With Stats

DBCC CLONEDATABASE ('AdventureWorks2014', 'AdventureWorks2014_CloneDB')

Message:

Database cloning for ‘AdventureWorks2014’ has started with target as ‘AdventureWorks2014_CloneDB’.

Database cloning for ‘AdventureWorks2014’ has finished. Cloned database is ‘AdventureWorks2014_CloneDB’.

Database ‘AdventureWorks2014_CloneDB’ is a cloned database. A cloned database should be used for diagnostic purposes only and is not supported for use in a production environment.

DBCC execution completed. If DBCC printed error messages, contact your system administrator.
 

–> I’ll create one more Clone Database without Stats:

-- Without Stats

DBCC CLONEDATABASE ('AdventureWorks2014', 'AdventureWorks2014_CloneDB_No_Stats')
WITH NO_STATISTICS, NO_QUERYSTORE

dbcc-clonedatabase
 

–> Let’s check the file size of all 3 Databases:

– The 1st image shows the size of original AdventureWorks2014 database i.e. 207 MB

– And 2nd and 3rd shows the size of other two Clone Databases i.e. just 16 MB.

dbcc-clonedb-01

dbcc-clonedb-02

dbcc-clonedb-03

 

–> Now we will check the Execution Plans of a query on all these three databases:

-- Check Execution plan on below T-SQL query in all 3 databases:

SELECT 
	P.BusinessEntityID, P.Title, P.FirstName, P.MiddleName, P.LastName, 
	E.BirthDate, E.Gender, E.HireDate, E.JobTitle, E.MaritalStatus, 
	D.Name
FROM [Person].[Person] P
INNER JOIN [HumanResources].[Employee] E ON E.BusinessEntityID = P.BusinessEntityID
CROSS APPLY (
	SELECT TOP 1 DepartmentID
	FROM [HumanResources].[EmployeeDepartmentHistory] DH 
	WHERE DH.BusinessEntityID = E.BusinessEntityID 
	ORDER BY StartDate DESC) EDH
INNER JOIN [HumanResources].[Department] D ON D.DepartmentID = EDH.DepartmentID

 

– On executing the above query on original AdventureWorks2014 database & AdventureWorks2014_CloneDB it shows same execution plan, like it shows:

1. Hash Match operator
2. 72% cost on Person PK
3. 18% cost on EmployeeDepartmentHistory PK

dbcc-clonedb-04
(click on the image to expand)

– But on executing the same query on AdventureWorks2014_CloneDB_No_Stats it shows different execution plan, here it shows:

1. Nested Loop operator
2. 92% cost on Person PK
3. 5% cost on EmployeeDepartmentHistory PK

dbcc-clonedb-05
(click on the image to expand)


SQL Error – SQL Server service failed to Start | Windows could not start the SQL Server

December 15, 2016 3 comments

 
Today I was trying to connect to a SQL Server instance of my DEV machine from SSMS, it took bit more time than usual and threw me an error:

Cannot connect to [SQL_Instance_name], A network-related or instance-specific error occurred while establishing a connection to SQL Server. The server was not found or was not accessible. Verify that the instance name is correct and that SQL Server is configured to allow remote connections. (provider: Named Pipes Provider, error: 40 – Could not open a connection to SQL Server) (Microsoft SQL Server, Error: 2)

 

I immediately checked SQL Services, and yes the SQL Server service was not running. But when I tried to run the service it didn’t turn up and it gave me an error:

Windows could not start the SQL Server (MSSQLSERVER) on Local Computer. For more information, review the System Event Log. If this is a non-Microsoft service, contact the service vendor, and refer to service-specific error code 14.

sqlservicesdown
 

Now, the only thing to know what would have happened is the Event viewer.

–> You can open “Event Viewer” by any of the below options:

1. Shortcut: Eventvwr.msc

2. Type “Event Viewer” in search box on Windows 8 and above.

3. Open Control Panel –> System and Maintenance –> Administrative Tools –> Event Viewer
 

Now on the “Event Viewer” window go to: Windows Logs –> Application

Check the logs on the General or Details tab:

eventviewer-for-sqlserver

I checked all errors and it threw following errors in sequence:

Error: 49910, Severity: 10, State: 1. (Params:). The error is printed in terse mode because there was error during formatting. Tracing, ETW, notifications etc are skipped.

Error: 17312, Severity: 16, State: 1. (Params:). The error is printed in terse mode because there was error during formatting. Tracing, ETW, notifications etc are skipped.

Error: 17300, Severity: 16, State: 1. (Params:). The error is printed in terse mode because there was error during formatting. Tracing, ETW, notifications etc are skipped.

Error: 33086, Severity: 10, State: 1. (Params:). The error is printed in terse mode because there was error during formatting. Tracing, ETW, notifications etc are skipped.

–> So, if you query these errors in sys.messages then you will see that one of the error (id = 17300) is related to insufficient memory:

select * 
from sys.messages 
where language_id = 1033 
and message_id IN (49910,17312, 17300, 33086)

SQL Server was unable to run a new system task, either because there is insufficient memory or the number of configured sessions exceeds the maximum allowed in the server. Verify that the server has adequate memory. Use sp_configure with option ‘user connections’ to check the maximum number of user connections allowed. Use sys.dm_exec_sessions to check the current number of sessions, including user processes.

 

–> Let’s also check SQL Server ERROR LOGS, go to Error Log location on you SQL Server machine: C:\Program Files\Microsoft SQL Server \MSSQL11.MSSQLSERVER \MSSQL\Log

I’ve removed unnecessary part here as the error log was too long, highlighted the real cause of the issue, and that is: Failed allocate pages: FAIL_PAGE_ALLOCATION 1.


2016-12-15 09:34:14.82 Server SQL Server detected 2 sockets with 10 cores per socket and 10 logical processors per socket, 20 total logical processors; using 20 logical processors based on SQL Server licensing. This is an informational message; no user action is required.
2016-12-15 09:34:14.82 Server SQL Server is starting at normal priority base (=7). This is an informational message only. No user action is required.
2016-12-15 09:34:14.82 Server Detected 143359 MB of RAM. This is an informational message; no user action is required.

2016-12-15 09:34:15.27 Server Using dynamic lock allocation. Initial allocation of 2500 Lock blocks and 5000 Lock Owner blocks per node. This is an informational message only. No user action is required.
2016-12-15 09:34:15.27 Server Lock partitioning is enabled. This is an informational message only. No user action is required.
2016-12-15 09:34:20.30 Server Failed allocate pages: FAIL_PAGE_ALLOCATION 1
2016-12-15 09:31:14.07 Server
Process/System Counts Value
—————————————- ———-
Available Physical Memory 145982603264
Available Virtual Memory 140678812086272
Available Paging File 167077097472
Working Set 337784832
Percent of Committed Memory in WS 100
Page Faults 94990
System physical memory high 1
System physical memory low 0
Process physical memory low 1
Process virtual memory low 0
2016-12-15 09:31:14.07 Server Error: 49910, Severity: 10, State: 1. (Params:). The error is printed in terse mode because there was error during formatting. Tracing, ETW, notifications etc are skipped.

2016-12-15 09:31:14.08 Server
MEMORYCLERK_SQLGENERAL (node 0) KB
—————————————- ———-
VM Reserved 0
VM Committed 0
Locked Pages Allocated 0
SM Reserved 0
SM Committed 0
Pages Allocated 1240
2016-12-15 09:31:14.08 Server Error: 17312, Severity: 16, State: 1. (Params:). The error is printed in terse mode because there was error during formatting. Tracing, ETW, notifications etc are skipped.
2016-12-15 09:31:14.08 Server SQL Server shutdown has been initiated

2016-12-15 09:31:14.08 Server
MEMORYCLERK_SQLCONNECTIONPOOL (node 0) KB
—————————————- ———-
VM Reserved 0
VM Committed 0
Locked Pages Allocated 0
SM Reserved 0
SM Committed 0
Pages Allocated 48
2016-12-15 09:31:14.08 Server Error: 17300, Severity: 16, State: 1. (Params:). The error is printed in terse mode because there was error during formatting. Tracing, ETW, notifications etc are skipped.

2016-12-15 09:31:14.08 Server
MEMORYCLERK_SNI (node 0) KB
—————————————- ———-
VM Reserved 0
VM Committed 0
Locked Pages Allocated 0
SM Reserved 0
SM Committed 0
Pages Allocated 16
2016-12-15 09:31:14.08 Server Error: 17300, Severity: 16, State: 1. (Params:). The error is printed in terse mode because there was error during formatting. Tracing, ETW, notifications etc are skipped.

MEMORYCLERK_SQLXP (node 0) KB
—————————————- ———-
VM Reserved 0
VM Committed 0
Locked Pages Allocated 0
SM Reserved 0
SM Committed 0
Pages Allocated 16
2016-12-15 09:31:14.08 Server Error: 17300, Severity: 16, State: 1. (Params:). The error is printed in terse mode because there was error during formatting. Tracing, ETW, notifications etc are skipped.

2016-12-15 09:31:14.08 Server
MEMORYCLERK_SOSNODE (Total) KB
—————————————- ———-
VM Reserved 0
VM Committed 0
Locked Pages Allocated 0
SM Reserved 0
SM Committed 0
Pages Allocated 26888
2016-12-15 09:31:14.08 Server Error: 17300, Severity: 16, State: 1. (Params:). The error is printed in terse mode because there was error during formatting. Tracing, ETW, notifications etc are skipped.
2016-12-15 09:31:14.08 Server
MEMORYCLERK_SOSOS (node 0) KB
—————————————- ———-
VM Reserved 0
VM Committed 0
Locked Pages Allocated 0
SM Reserved 0
SM Committed 0
Pages Allocated 192
2016-12-15 09:31:14.08 Server Error: 17312, Severity: 16, State: 1. (Params:). The error is printed in terse mode because there was error during formatting. Tracing, ETW, notifications etc are skipped.
MEMORYCLERK_SOSMEMMANAGER (node 0) KB
—————————————- ———-
VM Reserved 480
VM Committed 336
Locked Pages Allocated 0
SM Reserved 0
SM Committed 0
Pages Allocated 0
2016-12-15 09:31:14.08 Server SQL Server shutdown has been initiated

2016-12-15 09:31:14.08 Server
MEMORYCLERK_XE (node 0) KB
—————————————- ———-
VM Reserved 0
VM Committed 0
Locked Pages Allocated 0
SM Reserved 0
SM Committed 0
Pages Allocated 376
2016-12-15 09:31:14.08 Server Error: 33086, Severity: 10, State: 1. (Params:). The error is printed in terse mode because there was error during formatting. Tracing, ETW, notifications etc are skipped.
2016-12-15 09:31:14.08 Server
MEMORYCLERK_SQLLOGPOOL (node 0) KB
—————————————- ———-
VM Reserved 0
VM Committed 0
Locked Pages Allocated 0
SM Reserved 0
SM Committed 0
Pages Allocated 152
2016-12-15 09:31:14.08 Server Error: 17312, Severity: 16, State: 1. (Params:). The error is printed in terse mode because there was error during formatting. Tracing, ETW, notifications etc are skipped.
2016-12-15 09:31:14.08 Server SQL Server shutdown has been initiated

In the Error Log above you can also see the Error IDs we saw in Event Log, I’ve highlighted them with the Memory Clerks.
 

–> Now let’s wee if we can start SQL Server with minimal configuration by applying the Startup Parameter “-f”:

Open SQL Server Configuration Manager (SSCM) –> select “SQL Server Services” –> right click on SQL Server service, and select Properties.

sqlserverconfigmgr

Add “-f” as Startup Parameter, as shown below.

startupparam-f

Again go back to the SSCM and Start the SQL Server service, this time it will start as you have set SQL Server to run with minimum configuration, and thus it will run on limited memory.
 

–> Now I opened the SSMS and connected to the respective instance, under Object Explorer right click on Instance name, and selected Properties. Moved to the Memory page and checked the Maximum server memory (in MB) setting. It was just 128 MB, so I increased it to 110 GB as my server RAM was 140 GB.

sqlservermemory
 

–> Again went to the SSCM and removed the Startup Parameter “-f”, and restarted SQL Server services.

Now I was able to login to SQL Server instance without any issues !!!


SQL Error – Windows could not start the SQL Server (MSSQLSERVER) on Local Computer (moved Master DB)

June 29, 2016 1 comment

 
I was trying to move my Master DBs to another folder by using steps mentioned in my one of [previous blog post]. But after all steps, when I tried to Start the services I got error with following popup:

Master DB move 01

Error Description:

Windows could not start the SQL Server (MSSQLSERVER) on Local Computer. For more information, review the System Event Log. If this is a non-Microsoft service, contact the service vendor, and refer to service-specific error code 3417.
 

–> So, I checked the error log file and it showed the reason for error.
Default location: C:\Program Files\Microsoft SQL Server\MSSQL13.MSSQLSERVER\MSSQL\Log\


2016-06-27 12:18:28.02 Server The service account is ‘NT Service\MSSQLSERVER’. This is an informational message; no user action is required.
2016-06-27 12:13:33.30 Server Registry startup parameters:
     -d E:\SystemDatabases\Master\master.mdf
     -e C:\Program Files\Microsoft SQL Server\MSSQL13.MSSQLSERVER\MSSQL\Log\ERRORLOG
     -l E:\SystemDatabases\Master\mastlog.ldf
2016-06-27 12:13:33.30 Server Command Line Startup Parameters:
     -s “MSSQLSERVER”

2016-06-27 12:13:33.41 spid5s [INFO] HkHostDbCtxt::Initialize(): Database ID: [1] ‘master’. XTP Engine version is 0.0.
2016-06-27 12:18:28.12 spid5s Starting up database ‘master’.
2016-06-27 12:18:28.13 spid5s Error: 17204, Severity: 16, State: 1.
2016-06-27 12:18:28.13 spid5s FCB::Open failed: Could not open file E:\SystemDatabases\Master\master.mdf for file number 1. OS error: 5(Access is denied.).
2016-06-27 12:18:28.13 spid5s Error: 5120, Severity: 16, State: 101.
2016-06-27 12:18:28.13 spid5s Unable to open the physical file “E:\SystemDatabases\Master\master.mdf”. Operating system error 5: “5(Access is denied.)”.
2016-06-27 12:18:28.13 spid5s Error: 17204, Severity: 16, State: 1.
2016-06-27 12:18:28.13 spid5s FCB::Open failed: Could not open file E:\SystemDatabases\Master\mastlog.ldf for file number 2. OS error: 5(Access is denied.).
2016-06-27 12:18:28.13 spid5s Error: 5120, Severity: 16, State: 101.
2016-06-27 12:18:28.13 spid5s Unable to open the physical file “E:\SystemDatabases\Master\mastlog.ldf”. Operating system error 5: “5(Access is denied.)”.
2016-06-27 12:18:28.13 spid5s SQL Server shutdown has been initiated

 

–> The above error log (in bold) tells that the service account NT Service\MSSQLSERVER does not have access to the files moved to new location.

–> So, to provide access, go to the new folder location –> Right click and select Properties –> Go to Security tab, click on Edit –> click on Add, to add the Service Account. Apply the Service Account (here in my case NT Service\MSSQLSERVER) and change the Locations to your PC, as its a local Service Account:

Master DB move 02

Give “Full Control”, and click OK on popups.
 

Now Start the “SQL Server” services and this time it will work.

To check and confirm the new file location of Master DB, Execute following SQL query:

USE master
GO

SELECT *
FROM sys.database_files

Master DB move 03
 


Categories: DBA Stuff, SQL Errors Tags:

SQL DBA – Move master Database to another drive – in simple steps

June 28, 2016 2 comments

 
Well, there are times when you want to move your master database from the default location to some other drive. Now this activity cannot be done with the normal ALTER DATABASE statement with MODIFY FILE option. And you need a spacial handling for this case of master DB.
 


 

–> Let’s first check the location of master DB:

USE master
GO

SELECT * FROM sys.database_files

Move Master 01
 

–> Now leave SSMS, and open SSCM i.e. SQL Server Configuration Manager. Here select “SQL Server Service”, and Rigth Click on the instance of SQL Server, and choose Properties. Now select the Startup Parameters tab.

Move Master 02

Here you will see 3 line items:

1. -d is the path of the master data file.

2. -e is the path of the SQL error log file.

3. -l is the path of the master log file.

So, you need to update the 1st and 3rd ones. As I want to move my files to E:\SystemDatabases\Master\ location, so you just need to replace the existing path with following:

1. master data File:
-dC:\Program Files\Microsoft SQL Server\MSSQL13.MSSQLSERVER\MSSQL\DATA\master.mdf
-dE:\SystemDatabases\Master\master.mdf

2. master Log File:
-lC:\Program Files\Microsoft SQL Server\MSSQL13.MSSQLSERVER\MSSQL\DATA\mastlog.ldf
-lE:\SystemDatabases\Master\mastlog.ldf
 

–> Now Stop the SQL Server services, by going to: RUN –> services.msc

–> Manually Copy the master.mdf & mastlog.ldf files to the new location

–> Start the SQL Server services.

–> To confirm the new location, just execute following query and check the path:

USE master
GO

SELECT * FROM sys.database_files

Master DB move 03
 


Categories: DBA Stuff Tags: