CogKnowHow

Product:

Microsoft SQL server

Issue:
SQL server is slow, is it low on memory?

Solution:

Get Brent Ozar Health check.  https://www.brentozar.com/blitz/ 

Other solution:

Check if SQL server need to move pages out of memory with this code:

SELECT *

FROM sys.dm_os_performance_counters

WHERE [counter_name] = 'Page life expectancy'

“Page Life Expectancy drops can be triggered by confusing operations. By default, any one running query can get a memory grant the size of 25% of your buffer pool. Run a few of those queries at the same time, and your buffer pool gets drained – but PLE doesn’t necessarily drop. However, the instant an unrelated query runs and needs to get data that isn’t cached in RAM, your PLE will drop catastrophically. Which queries are at fault? ”

Check how memory is used by each database:

SELECT

    (CASE WHEN ([database_id] = 32767)

        THEN N'Resource Database'

        ELSE DB_NAME ([database_id]) END) AS [DatabaseName],

    COUNT (*) * 8 / 1024 AS [MBUsed],

    SUM (CAST ([free_space_in_bytes] AS BIGINT)) / (1024 * 1024) AS [MBEmpty]

FROM sys.dm_os_buffer_descriptors

GROUP BY [database_id];

GO

More Information:

https://www.brentozar.com/archive/2020/06/page-life-expectancy-doesnt-mean-jack-and-you-should-stop-looking-at-it/

https://houseofbrick.com/page-life-expectancy-and-what-its-telling-you/

https://www.spotlightcloud.io/blog/monitoring-page-life-expectancy-in-sql-server

https://training.brentozar.com/p/how-i-use-the-first-responder-kit

SQL SERVER – What is Page Life Expectancy (PLE) Counter

https://www.sqlskills.com/blogs/paul/performance-issues-from-wasted-buffer-pool-memory/

https://github.com/SQLadmin/AwesomeSQLServer/blob/master/T-SQL%20Scripts/Memory%20Monitoring.sql

Product:

Microsoft SQL server

Issue:
How slow is the disk for my databases?

Suggested solution:

This query will show Average Total Latency for each database, value above 10ms is bad.

SELECT DB_NAME(vfs.database_id) AS database_name ,physical_name AS [Physical Name],

size_on_disk_bytes / 1024 / 1024. AS [Size of Disk] ,

CAST(io_stall_read_ms/(1.0 + num_of_reads) AS NUMERIC(10,1)) AS [Average Read latency] ,

CAST(io_stall_write_ms/(1.0 + num_of_writes) AS NUMERIC(10,1)) AS [Average Write latency] ,

CAST((io_stall_read_ms + io_stall_write_ms)

/(1.0 + num_of_reads + num_of_writes)

AS NUMERIC(10,1)) AS [Average Total Latency],

num_of_bytes_read / NULLIF(num_of_reads, 0) AS [Average Bytes Per Read],

num_of_bytes_written / NULLIF(num_of_writes, 0) AS [Average Bytes Per Write]

FROM sys.dm_io_virtual_file_stats(NULL, NULL) AS vfs

JOIN sys.master_files AS mf

ON vfs.database_id = mf.database_id AND vfs.file_id = mf.file_id

ORDER BY [Average Total Latency] DESC

More information:

https://www.sqlshack.com/sql-server-troubleshooting-disk-i-o-problems/

https://www.mssqltips.com/sqlservertip/6125/disk-latency-for-sql-server-database-and-transaction-log-files/

https://www.brentozar.com/blitz/slow-storage-reads-writes/

Product:

Microsoft SQL server

Issue:

Can i list when all databases where backed up?

Solution:

Enter a Query;

SELECT

    bs.database_name,

bs.backup_size,

    bs.backup_start_date,

    bs.backup_finish_date,

    bs.server_name, 

    bs.user_name,

    bs.type,

    bm.physical_device_name

FROM msdb.dbo.backupset AS bs

INNER JOIN msdb.dbo.backupmediafamily AS bm on bs.media_set_id = bm.media_set_id

More information:

https://www.mssqltips.com/sqlservertip/3171/identify-sql-server-databases-that-are-no-longer-in-use/

https://www.mssqltips.com/sqlservertip/1601/script-to-retrieve-sql-server-database-backup-history-and-no-backups/

Getting database backup history in SQL Server

How to automate SQL Server database backups

https://ola.hallengren.com/sql-server-backup.html

Product:
Microsoft SQL Server

Issue:

How list users in a database?

Suggestion:

To get all users in one database;

use [database_name]
select name as username,
       create_date,
       modify_date,
       type_desc as type,
       authentication_type_desc as authentication_type
from sys.database_principals
where type not in ('A', 'G', 'R', 'X')
      and sid is not null
      and name != 'guest'
order by username;

To get all users on the SQL server;

declare @db varchar(100)
declare @user varchar(100)
declare c cursor for select name from sys.sysdatabases        

open c

fetch next from c into @db

while @@fetch_status = 0
begin
    print @db   
    exec ('use ' + @db)

    declare u cursor for select name from sys.sysusers
        where issqlrole <> 1 and hasdbaccess <> 0 and isntname <> 1

    open u   

    fetch next from u into @user

    while @@fetch_status = 0
    begin
        print @user
        fetch next from u into @user
    end

    print '--------------------------------------------------'
    close u     
    deallocate u    
    fetch next from c into @db
end

close c
deallocate c

 

To list the DB_OWNERS in database, use this code:

SELECT user_name(member_principal_id)

FROM   sys.database_role_members

WHERE  user_name(role_principal_id) = 'db_owner'

To get more information, you can query like this:

SELECT  members.name MemberName, roles.name,roles.type_desc,members.type_desc

FROM sys.database_role_members rolemem

INNER JOIN sys.database_principals roles

    ON rolemem.role_principal_id = roles.principal_id

INNER JOIN sys.database_principals members

    ON rolemem.member_principal_id = members.principal_id

where 

 roles.name like  'db_owner'

To find out who is sysadmin on the SQL database:

SELECT createdate,accdate, name FROM sys.syslogins WHERE sysadmin = 1

More Information:

https://stackoverflow.com/questions/2445444/how-to-get-a-list-of-users-for-all-instances-databases

https://dev.to/jsgurugit/list-users-in-sql-server-database-1k20

https://docs.microsoft.com/en-us/sql/relational-databases/system-catalog-views/sys-database-role-members-transact-sql?view=sql-server-ver15

https://www.sqlserver-dba.com/2015/05/find-database-users-mapped-to-db_owner-role.html

List of Users with db_owner Role in All Databases

https://www.mssqltips.com/sqlservertip/6828/sql-server-login-user-permissions-fn-my-permissions/

Product:
Microsoft SQL server

Issue:
How to simple move database file to other hard disk?

Suggested solution:

There are many ways to do this task, this is one of them:

Detach the database with a SQL query:

Use MASTER
GO

-- Set database to single user mode
ALTER DATABASE adventure
SET SINGLE_USER
GO 

-- Detach the database
sp_detach_db 'Adventure'
GO

Copy the files with robocopy from a command prompt:

Syntax are : ROBOCOPY source destination [file [file]…] [options]

The /MOV parameter will move the file, if you leave it out – there will be a copy instead.

This will move file adventure.mdf from C to D drive.

robocopy /MOV "C:\Program Files\Microsoft SQL Server\MSSQL13.MSSQLSERVER\MSSQL\DATA"  D:\Data   adventure.mdf

This will move file adventure.ldf from C to L drive.

robocopy /MOV "C:\Program Files\Microsoft SQL Server\MSSQL13.MSSQLSERVER\MSSQL\DATA"  L:\Log   adventure.ldf

You need to put file path in ” if they contain spaces.

Attach the database with a SQL query:

USE master
GO

-- Attach the database
sp_attach_DB 'Adventure', 
'D:\data\Adventure.mdf',
'L:\log\Adventure.ldf'
GO

More Information:

Robocopy does NOT like trailing \

The Ultimate Guide to Robocopy

https://dba.stackexchange.com/questions/52007/how-do-i-move-sql-server-database-files

https://docs.microsoft.com/en-us/sql/relational-databases/databases/move-user-databases?view=sql-server-2017

https://www.mssqltips.com/sqlservertip/1774/move-sql-server-transaction-log-files-to-a-different-location-via-tsql-and-ssms/

How to Move Log File or MDF File in SQL Server? – Interview Question of the Week #208

Product:

VirtualBox https://www.virtualbox.org/wiki/Downloads

Microsoft Windows 10

Issue:
How stop virtual box vms from command line before computer shutdown?

Suggestion: (this may not work)

Create text files in a c:\scripts folder with the command you need to start and stop vms.
Important: that case of the vms name matched the name you have given them inside Virtualbox.

Create a CMD file with following command:

rem stop one virtualbox image
"C:\Program Files\Oracle\VirtualBox\VBoxManage.exe" list runningvms

"C:\Program Files\Oracle\VirtualBox\VBoxManage.exe" controlvm "win2012big" acpipowerbutton
"C:\Program Files\Oracle\VirtualBox\VBoxManage.exe" controlvm "Win2016 CAPA" acpipowerbutton

Add the file to group policy on the computer:

1. In a command window, open the Group Policy Editor (GPE) by running gpedit.msc.
2. Expand Computer Configuration and select Windows Settings.
3. Double-click Scripts (Startup/Shutdown).
4. Click Add and add c:/scripts/vboxshutdown.cmd.

Add the start script (c:/scripts/vboxstart.cmd) to the Start properties.

Create a CMD file with following command to start:

rem start one virtualbox image
"C:\Program Files\Oracle\VirtualBox\VBoxManage.exe" startvm "Win2016 CAPA"
"C:\Program Files\Oracle\VirtualBox\VBoxManage.exe" startvm "Win2019"

You may need to use the Task Scheduler instead, to make it work.

Or try placing a shortcut of the script as a startup program in %APPDATA%\Microsoft\Windows\Start Menu\Programs\Startup.

Or place a shortcut to your start script in folder C:\ProgramData\Microsoft\Windows\Start Menu\Programs\StartUp – that make the script run when user login.

More Information:

https://askubuntu.com/questions/457329/shutting-down-all-virtualbox-vagrant-vms-in-one-easy-to-use-bash-command-that  

https://docs.microsoft.com/en-us/previous-versions/windows/it-pro/windows-server-2012-r2-and-2012/dn789196(v=ws.11)

https://simplecodesoftware.com/articles/how-to-set-up-group-policy-scripts-programmatically

Vboxmanage command not found in Windows CMD or PowerShell

https://www.windowscentral.com/how-create-automated-task-using-task-scheduler-windows-10

https://4sysops.com/archives/managing-virtualbox-vms-with-powershell/

http://desertpenguin.org/blog/nnvirtualboxpowershellmodul.html

https://github.com/SmithersTheOracle/VirtualBoxPS

Managing VirtualBox with PowerShell