functions/Get-DbaDbVirtualLogFile.ps1
|
function Get-DbaDbVirtualLogFile { <# .SYNOPSIS Returns database virtual log file information for database files on a SQL instance. .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/transaction-log-vlfs-too-many-or-too-few/ http://blogs.msdn.com/b/saponsqlserver/archive/2012/02/22/too-many-virtual-log-files-vlfs-can-cause-slow-database-recovery.aspx If you've got a high number of VLFs, you can use Expand-SqlTLogResponsibly to reduce the number. .PARAMETER SqlInstance Specifies the SQL Server instance(s) to scan. .PARAMETER SqlCredential Allows you to login to servers using SQL Logins instead of Windows Authentication (AKA Integrated or Trusted). To use: $scred = Get-Credential, then pass $scred object to the -SqlCredential parameter. Windows Authentication will be used if SqlCredential is not specified. SQL Server does not accept Windows credentials being passed as credentials. To connect as a different Windows user, run PowerShell as that user. .PARAMETER Database Specifies the database(s) to process. Options for this list are auto-populated from the server. If unspecified, all databases will be processed. .PARAMETER ExcludeDatabase Specifies the database(s) to exclude from processing. Options for this list are auto-populated from the server. .PARAMETER IncludeSystemDBs If this switch is enabled, system database information will be displayed. .PARAMETER EnableException By default, when something goes wrong we try to catch it, interpret it and give you a friendly warning message. This avoids overwhelming you with "sea of red" exceptions, but is inconvenient because it basically disables advanced scripting. Using this switch turns this "nice by default" feature off and enables you to catch exceptions with your own try/catch. .NOTES Tags: VLF, Database, LogFile Website: https://dbatools.io Copyright: (C) Chrissy LeMaire, clemaire@gmail.com License: GNU GPL v3 https://opensource.org/licenses/GPL-3.0 .LINK https://dbatools.io/Get-DbaDbVirtualLogFile .EXAMPLE Get-DbaDbVirtualLogFile -SqlInstance sqlcluster Returns all user database virtual log file counts for the sqlcluster instance. .EXAMPLE Get-DbaDbVirtualLogFile -SqlInstance sqlserver | Where-Object {$_.Count -ge 50} Returns user databases that have 50 or more VLFs. .EXAMPLE @('sqlserver','sqlcluster') | Get-DbaDbVirtualLogFile Returns all VLF information for the sqlserver and sqlcluster SQL Server instances. Processes data via the pipeline. .EXAMPLE Get-DbaDbVirtualLogFile -SqlInstance sqlcluster -Database db1, db2 Returns the VLF counts for the db1 and db2 databases on sqlcluster. #> [CmdletBinding()] [OutputType([System.Collections.ArrayList])] param ([parameter(ValueFromPipeline, Mandatory = $true)] [Alias("ServerInstance", "SqlServer")] [DbaInstanceParameter[]]$SqlInstance, [PSCredential]$SqlCredential, [Alias("Databases")] [object[]]$Database, [object[]]$ExcludeDatabase, [switch]$IncludeSystemDBs, [switch][Alias('Silent')]$EnableException ) process { foreach ($instance in $SqlInstance) { try { Write-Message -Level Verbose -Message "Connecting to $instance." $server = Connect-SqlInstance -SqlInstance $instance -SqlCredential $sqlcredential } catch { Stop-Function -Message "Failure" -Category ConnectionError -ErrorRecord $_ -Target $instance -Continue } $dbs = $server.Databases if ($Database) { $dbs = $dbs | Where-Object Name -in $Database } if ($ExcludeDatabase) { $dbs = $dbs | Where-Object Name -NotIn $ExcludeDatabase } if (!$IncludeSystemDBs) { $dbs = $dbs | Where-Object IsSystemObject -eq $false } foreach ($db in $dbs) { try { $data = $db.Query("DBCC LOGINFO") foreach ($d in $data) { [pscustomobject]@{ ComputerName = $server.NetName InstanceName = $server.ServiceName SqlInstance = $server.DomainInstanceName Database = $db.Name RecoveryUnitId = $d.RecoveryUnitId FileId = $d.FileId FileSize = $d.FileSize StartOffset = $d.StartOffset FSeqNo = $d.FSeqNo Status = $d.Status Parity = $d.Parity CreateLsn = $d.CreateLSN } } } catch { Stop-Function -Message "Unable to query $($db.name) on $instance." -ErrorRecord $_ -Target $db -Continue } } } } } |