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Get-DbaDbVirtualLogFile

Mon Jan 13, 2020 11:00 am

NAME Get-DbaDbVirtualLogFile



SYNOPSIS

Returns database virtual log file information for database files on a SQL instance.





SYNTAX

Get-DbaDbVirtualLogFile [-SqlInstance] <Sqlcollaborative.Dbatools.Parameter.DbaInstanceParameter[]>

[[-SqlCredential] <Pscredential>] [[-Database] <System.Object[]>] [[-ExcludeDatabase] <System.Object[]>]

[-IncludeSystemDBs <Switch>] [-EnableException <Switch>] [<CommonParameters>]





DESCRIPTION

Having a transaction log file with too many virtual log files (VLFs) can hurt database performance.



Too many VLFs can cause transaction log backups to slow down and can also slow down database recovery and, in

extreme cases, even affect insert/update/delete performance.



References:



http://www.sqlskills.com/blogs/kimberly ... r-too-few/



http://blogs.msdn.com/b/saponsqlserver/ ... database-r

ecovery.aspx



If you've got a high number of VLFs, you can use Expand-SqlTLogResponsibly to reduce the number.





PARAMETERS

-Database [<System.Object[]>]

Specifies the database(s) to process. Options for this list are auto-populated from the server. If

unspecified, all databases will be processed.



Required? false

Position? named

Default value

Accept pipeline input? False

Accept wildcard characters? false



-EnableException [<Switch>]

By default, when something goes wrong we try to catch it, interpret it and give you a friendly warning message.

This avoids overwhelming you with "sea of red" exceptions, but is inconvenient because it basically disables

advanced scripting.

Using this switch turns this "nice by default" feature off and enables you to catch exceptions with your own

try/catch.



Required? false

Position? named

Default value

Accept pipeline input? False

Accept wildcard characters? false



-ExcludeDatabase [<System.Object[]>]

Specifies the database(s) to exclude from processing. Options for this list are auto-populated from the server.



Required? false

Position? named

Default value

Accept pipeline input? False

Accept wildcard characters? false



-IncludeSystemDBs [<Switch>]

If this switch is enabled, system database information will be displayed.



Required? false

Position? named

Default value

Accept pipeline input? False

Accept wildcard characters? false



-SqlCredential [<Pscredential>]

Login to the target instance using alternative credentials. Accepts PowerShell credentials (Get-Credential).



Windows Authentication, SQL Server Authentication, Active Directory - Password, and Active Directory -

Integrated are all supported.



For MFA support, please use Connect-DbaInstance.



Required? false

Position? named

Default value

Accept pipeline input? False

Accept wildcard characters? false



-SqlInstance [<Sqlcollaborative.Dbatools.Parameter.DbaInstanceParameter[]>]

The target SQL Server instance or instances.



Required? false

Position? named

Default value

Accept pipeline input? False

Accept wildcard characters? false



<CommonParameters>

This cmdlet supports the common parameters: Verbose, Debug,

ErrorAction, ErrorVariable, WarningAction, WarningVariable,

OutBuffer, PipelineVariable, and OutVariable. For more information, see

about_CommonParameters (https:/go.microsoft.com/fwlink/?LinkID=113216).



INPUTS



OUTPUTS

System.Collections.ArrayList





NOTES





Tags: VLF, Database, LogFile

Author: Chrissy LeMaire (@cl), netnerds.net



Website: https://dbatools.io

Copyright: (c) 2018 by dbatools, licensed under MIT

License: MIT https://opensource.org/licenses/MIT



-------------------------- EXAMPLE 1 --------------------------



PS C:\\>Get-DbaDbVirtualLogFile -SqlInstance sqlcluster



Returns all user database virtual log file details for the sqlcluster instance.

-------------------------- EXAMPLE 2 --------------------------



PS C:\\>Get-DbaDbVirtualLogFile -SqlInstance sqlserver | Group-Object -Property Database | Where-Object Count -gt 50



Returns user databases that have 50 or more VLFs.

-------------------------- EXAMPLE 3 --------------------------



PS C:\\>'sqlserver','sqlcluster' | Get-DbaDbVirtualLogFile



Returns all VLF information for the sqlserver and sqlcluster SQL Server instances. Processes data via the pipeline.

-------------------------- EXAMPLE 4 --------------------------



PS C:\\>Get-DbaDbVirtualLogFile -SqlInstance sqlcluster -Database db1, db2



Returns the VLF counts for the db1 and db2 databases on sqlcluster.



RELATED LINKS

https://dbatools.io/Get-DbaDbVirtualLogFile