functions/Test-DbaVirtualLogFile.ps1
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function Test-DbaVirtualLogFile { <# .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 $scred object to the -SqlCredential parameter. Windows Authentication will be used if SqlCredential is not specified. SQL Server does not accept Windows credentials being passed as credentials. To connect as a different Windows user, run PowerShell as that user. .PARAMETER Database Specifies the database(s) to process. Options for this list are auto-populated from the server. If unspecified, all databases will be processed. .PARAMETER ExcludeDatabase Specifies the database(s) to exclude from processing. Options for this list are auto-populated from the server. .PARAMETER IncludeSystemDBs If this switch is enabled, system database information will be displayed. .PARAMETER Detailed If this switch is enabled, all information provided by DBCC LOGINFO plus the server name and database name is returned. .NOTES Tags: DisasterRecovery, Backup Website: https://dbatools.io Copyright: (C) Chrissy LeMaire, clemaire@gmail.com License: GNU GPL v3 https://opensource.org/licenses/GPL-3.0 .LINK https://dbatools.io/Test-DbaVirtualLogFile .EXAMPLE Test-DbaVirtualLogFile -SqlInstance sqlcluster Returns all user database virtual log file counts for the sqlcluster instance. .EXAMPLE Test-DbaVirtualLogFile -SqlInstance sqlserver | Where-Object {$_.Count -ge 50} Returns user databases that have 50 or more VLFs. .EXAMPLE @('sqlserver','sqlcluster') | Test-DbaVirtualLogFile Returns all VLF information for the sqlserver and sqlcluster SQL Server instances. Processes data via the pipeline. .EXAMPLE Test-DbaVirtualLogFile -SqlInstance sqlcluster -Database db1, db2 Returns 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]$Detailed ) PROCESS { foreach ($servername in $SqlInstance) { Write-Verbose "Connecting to $servername." try { $server = Connect-SqlInstance $servername -SqlCredential $SqlCredential } catch { Write-Warning "Can't connect to $instance, skipping." Continue } $dbs = $server.Databases #If IncludeSystemDBs is true, include systemdbs #only look at online databases (Status equal normal) if ($Database) { $dbs = $dbs | Where-Object { $Database -contains $_.Name } } if ($ExcludeDatabase) { $dbs = $dbs | Where-Object Name -notin $ExcludeDatabase } if ($IncludeSystemDBs) { $dbs = $dbs | Where-Object { $_.status -eq 'Normal' } } else { $dbs = $dbs | Where-Object { $_.status -eq 'Normal' -and $_.IsSystemObject -eq 0 } } foreach ($db in $dbs) { try { Write-Verbose "Querying $($db.name) on $servername." #Execute query against individual database and add to output if ($Detailed -eq $true) { $table = New-Object System.Data.Datatable $servercolumn = $table.Columns.Add("Server") $servercolumn.DefaultValue = $server.name $dbcolumn = $table.Columns.Add("Database") $dbcolumn.DefaultValue = $db.name $temptable = $db.ExecuteWithResults("DBCC LOGINFO").Tables foreach ($column in $temptable.Columns) { $null = $table.Columns.Add($column.ColumnName) } foreach ($row in $temptable.rows) { $table.ImportRow($row) } $table } else { [PSCustomObject]@{ Server = $server.name Database = $db.name Count = $db.ExecuteWithResults("DBCC LOGINFO").Tables.Rows.Count } } } catch { Write-Exception $_ Write-Warning "Unable to query $($db.name) on $servername." continue } } } } } |