functions/Get-DbaDbExtentDiff.ps1
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function Get-DbaDbExtentDiff { <# .SYNOPSIS What percentage of a database has changed since the last full backup .DESCRIPTION This is only an implementation of the script created by Paul S. Randal to find what percentage of a database has changed since the last full backup. https://www.sqlskills.com/blogs/paul/new-script-how-much-of-the-database-has-changed-since-the-last-full-backup/ .PARAMETER SqlInstance The target SQL Server instance .PARAMETER SqlCredential Login to the target instance using alternative credentials. Windows and SQL Authentication supported. Accepts credential objects (Get-Credential) .PARAMETER Database The database(s) to process - this list is auto-populated from the server. If unspecified, all databases will be processed. .PARAMETER ExcludeDatabase The database(s) to exclude - this list is auto-populated from the server .PARAMETER WhatIf Shows what would happen if the command were to run. No actions are actually performed. .PARAMETER Confirm Prompts you for confirmation before executing any changing operations within the command. .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 Author: Viorel Ciucu, viorel.ciucu@gmail.com, cviorel.com Website: https://dbatools.io Copyright: (C) Chrissy LeMaire, clemaire@gmail.com License: GNU GPL v3 https://opensource.org/licenses/GPL-3.0 .LINK http://dbatools.io/Get-DbaDbExtentDiff .EXAMPLE Get the changes for the DBA database. Get-DbaDbExtentDiff -SqlInstance SQL2016 -Database DBA .EXAMPLE Get the changes for the DB01 database on multiple servers. Get-DbaDbExtentDiff -SqlInstance $SQL2017N1, $SQL2017N2, $SQL2016 -Database DB01 -SqlCredential $Cred #> [CmdletBinding(SupportsShouldProcess = $true, ConfirmImpact = "High")] param ( [parameter(Mandatory = $true, ValueFromPipeline = $true)] [Alias('ServerInstance', 'SqlServer')] [DbaInstance[]]$SqlInstance, [PSCredential]$SqlCredential, [object[]]$Database, [object[]]$ExcludeDatabase, [switch]$EnableException ) begin { $rex = [regex]':(?<extent>[\d]+)\)' function Get-DbaExtent ([string[]]$field) { $res = 0 foreach ($f in $field) { $extents = $rex.Matches($f) if ($extents.Count -eq 1) { $res += 1 } else { $pages = [int]$extents[1].Groups['extent'].Value - [int]$extents[0].Groups['extent'].Value $res += $pages / 8 + 1 } } return $res } } process { foreach ($instance in $SqlInstance) { try { Write-Message -Level Verbose -Message "Connecting to $instance" $server = Connect-DbaInstance -SqlInstance $instance -SqlCredential $SqlCredential -NonPooled } 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 } $sourcedbs = @() foreach ($db in $dbs) { if ($db.IsAccessible -ne $true) { Write-Message -Level Verbose -Message "$db is not accessible on $instance, skipping" } else { $sourcedbs += $db } } if ($server.VersionMajor -ge 14 ) { foreach ($db in $sourcedbs) { $DBCCPageQueryDMV = " SELECT SUM(total_page_count) / 8 as [ExtentsTotal], SUM(modified_extent_page_count) / 8 as [ExtentsChanged], 100.0 * SUM(modified_extent_page_count)/SUM(total_page_count) as [ChangedPerc] FROM sys.dm_db_file_space_usage " $DBCCPageResults = $server.Query($DBCCPageQueryDMV, $db.Name) [pscustomobject]@{ ComputerName = $server.NetName InstanceName = $server.ServiceName SqlInstance = $server.DomainInstanceName DatabaseName = $db.Name ExtentsTotal = $DBCCPageResults.ExtentsTotal ExtentsChanged = $DBCCPageResults.ExtentsChanged ChangedPerc = [math]::Round($DBCCPageResults.ChangedPerc, 2) } } } else { $MasterFilesQuery = " SELECT [file_id], [size], database_id, db_name(database_id) as dbname FROM master.sys.master_files WHERE [type_desc] = N'ROWS' " $MasterFiles = $server.Query($MasterFilesQuery) $MasterFiles = $MasterFiles | Where-Object dbname -In $sourcedbs.Name $MasterFilesGrouped = $MasterFiles | Group-Object -Property dbname foreach ($db in $MasterFilesGrouped) { $sizeTotal = 0 $dbExtents = @() foreach ($results in $db.Group) { $extentID = 0 $sizeTotal = $sizeTotal + $results.size / 8 while ($extentID -lt $results.size) { $pageID = $extentID + 6 $DBCCPageQuery = "DBCC PAGE ('$($results.dbname)', $($results.file_id), $pageID, 3) WITH TABLERESULTS, NO_INFOMSGS" $DBCCPageResults = $server.Query($DBCCPageQuery) $dbExtents += $DBCCPageResults | Where-Object { $_.VALUE -eq ' CHANGED' -And $_.ParentObject -like 'DIFF_MAP*'} $extentID = $extentID + 511232 } } $extents = Get-DbaExtent $dbExtents.Field [pscustomobject]@{ ComputerName = $server.NetName InstanceName = $server.ServiceName SqlInstance = $server.DomainInstanceName DatabaseName = $db.Name ExtentsTotal = $sizeTotal ExtentsChanged = $extents ChangedPerc = [math]::Round(($extents / $sizeTotal * 100), 2) } } } } } } |