functions/Test-DbaIdentityUsage.ps1
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function Test-DbaIdentityUsage { <# .SYNOPSIS Displays information relating to IDENTITY seed usage. Works on SQL Server 2008 and above. .DESCRIPTION IDENTITY seeds have max values based off of their data type. This module will locate identity columns and report the seed usage. .PARAMETER SqlInstance Allows you to specify a comma separated list of servers to query. .PARAMETER SqlCredential Allows you to login to servers using SQL Logins as opposed to Windows Auth/Integrated/Trusted. To use: $cred = Get-Credential, this pass this $cred to the param. Windows Authentication will be used if DestinationSqlCredential is not specified. To connect as a different Windows user, run PowerShell as that user. .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 Threshold Allows you to specify a minimum % of the seed range being utilized. This can be used to ignore seeds that have only utilized a small fraction of the range. .PARAMETER NoSystemDb Allows you to suppress output on system databases .PARAMETER Silent Use this switch to disable any kind of verbose messages .NOTES Author: Brandon Abshire, netnerds.net Tags: Identity 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-DbaIdentityUsage .EXAMPLE Test-DbaIdentityUsage -SqlInstance sql2008, sqlserver2012 Check identity seeds for servers sql2008 and sqlserver2012. .EXAMPLE Test-DbaIdentityUsage -SqlInstance sql2008 -Database TestDB Check identity seeds on server sql2008 for only the TestDB database .EXAMPLE Test-DbaIdentityUsage -SqlInstance sql2008 -Database TestDB -Threshold 20 Check identity seeds on server sql2008 for only the TestDB database, limiting results to 20% utilization of seed range or higher #> [CmdletBinding()] Param ( [parameter(Position = 0, Mandatory = $true, ValueFromPipeline = $True)] [Alias("ServerInstance", "SqlServer", "SqlServers")] [DbaInstanceParameter[]]$SqlInstance, [PSCredential] $SqlCredential, [Alias("Databases")] [object[]]$Database, [object[]]$ExcludeDatabase, [parameter(Position = 1, Mandatory = $false)] [int]$Threshold = 0, [parameter(Position = 2, Mandatory = $false)] [switch]$NoSystemDb, [switch]$Silent ) BEGIN { $sql = ";WITH CTE_1 AS ( SELECT SCHEMA_NAME(o.schema_id) AS SchemaName, OBJECT_NAME(a.Object_id) as TableName, a.Name as ColumnName, seed_value AS SeedValue, CONVERT(bigint, increment_value) as IncrementValue, CONVERT(bigint, ISNULL(a.last_value, seed_value)) AS LastValue, CONVERT(bigint, ( CONVERT(bigint, ISNULL(last_value, seed_value)) - CONVERT(bigint, seed_value) + (CASE WHEN CONVERT(bigint, seed_value) <> 0 THEN 1 ELSE 0 END) ) / CONVERT(bigint, increment_value) ) AS NumberOfUses, -- Divide by increment_value to shows the max number of values that can be used -- E.g: smallint identity column that starts on the lower possible value (-32768) and have an increment of 2 will only accept ABS(32768 - 32767 - 1) / 2 = 32768 rows CAST( --ABS( CONVERT(bigint, seed_value) - Case When b.name = 'tinyint' Then 255 When b.name = 'smallint' Then 32767 When b.name = 'int' Then 2147483647 When b.name = 'bigint' Then 9223372036854775807 End - -- When less than 0 the 0 counts too CASE WHEN CONVERT(bigint, seed_value) <= 0 THEN 1 ELSE 0 END --) / CONVERT(bigint, increment_value) AS Numeric(20, 0)) AS MaxNumberRows FROM sys.identity_columns a INNER JOIN sys.objects o ON a.object_id = o.object_id INNER JOIN sys.types As b ON a.system_type_id = b.system_type_id WHERE a.seed_value is not null ), CTE_2 AS ( SELECT SchemaName, TableName, ColumnName, CONVERT(BIGINT, SeedValue) AS SeedValue, CONVERT(BIGINT, IncrementValue) AS IncrementValue, LastValue, ABS(CONVERT(FLOAT,MaxNumberRows)) AS MaxNumberRows, NumberOfUses, CONVERT(Numeric(18,2), ((CONVERT(Float, NumberOfUses) / ABS(CONVERT(FLOAT,MaxNumberRows)) * 100))) AS [PercentUsed] FROM CTE_1 ) SELECT DB_NAME() as DatabaseName, SchemaName, TableName, ColumnName, SeedValue, IncrementValue, LastValue, MaxNumberRows, NumberOfUses, [PercentUsed] FROM CTE_2" if ($Threshold -gt 0) { $sql += " WHERE [PercentUsed] >= " + $Threshold + " ORDER BY [PercentUsed] DESC" } else { $sql += " ORDER BY [PercentUsed] DESC" } } process { foreach ($instance in $SqlInstance) { Write-Message -Level Verbose -Message "Attempting to connect to $instance" try { $server = Connect-SqlInstance -SqlInstance $instance -SqlCredential $SqlCredential } catch { Stop-Function -Message "Failure" -Category ConnectionError -ErrorRecord $_ -Target $instance -Continue } if ($server.versionMajor -lt 10) { Stop-Function -Message "This function does not support versions lower than SQL Server 2008 (v10). Skipping server $instance." -Continue } $dbs = $server.Databases if ($Database) { $dbs = $dbs | Where-Object {$Database -contains $_.Name} } if ($ExcludeDatabase) { $dbs = $dbs | Where-Object Name -NotIn $ExcludeDatabase } if ($NoSystemDb) { $dbs = $dbs | Where-Object IsSystemObject -eq $false } foreach ($db in $dbs) { Write-Message -Level Verbose -Message "Processing $db on $instance" if ($db.IsAccessible -eq $false) { Stop-Function -Message "The database $db is not accessible. Skipping database." -Continue } foreach ($row in $db.ExecuteWithResults($sql).Tables[0]) { if ($row.PercentUsed -eq [System.DBNull]::Value) { continue } if ($row.PercentUsed -ge $threshold) { [PSCustomObject]@{ ComputerName = $server.NetName InstanceName = $server.ServiceName SqlInstance = $server.DomainInstanceName Database = $row.DatabaseName Schema = $row.SchemaName Table = $row.TableName Column = $row.ColumnName SeedValue = $row.SeedValue IncrementValue = $row.IncrementValue LastValue = $row.LastValue MaxNumberRows = $row.MaxNumberRows NumberOfUses = $row.NumberOfUses PercentUsed = $row.PercentUsed } } } } } } } |