Azure Runbook Workflow that finds fragmented database tables and re-indexes them

Sitecore-DB-Maintenance-Plan-Workflow-RB.ps1

workflow Sitecore-DB-Maintenance-Plan-Workflow-RB
{
    <#
    .SYNOPSIS
        Azure Runbook Workflow that finds fragmented database tables and re-indexes them
    .DESCRIPTION
        Finds any tables with a average fragmentation higher than the defined $FragPercentage and then indexes them
    .PARAMETER SqlServer
        Your SQL Server Name (e.g 'my-sql-server.database.windows.net')
    .PARAMETER Database
        Your Database (e.g 'sc103_Master')
    .PARAMETER SQLCredentialName
        Your Credentials name (e.g 'DatabaseCred')
    .PARAMETER FragPercentage
        The minimum average % fragmentation of tables to include (e.g '20')
    .PARAMETER SqlServerPort
        Your SQL Server Port (usually '1433')
    .PARAMETER RebuildOffline
        If the Rebuild should be carried out while the database is still accessible or not (use online to keep accessible)
    .PARAMETER Table
        Name of a single table that should be re-indexed only (e.g 'Items'). Leave empty for all tables.
    #>

    param(
        [parameter(Mandatory=$True)]
        [string] $SqlServer = "", ## Your SQL Server Name (e.g 'my-sql-server.database.windows.net')

        [parameter(Mandatory=$True)] ## Your Database (e.g 'sc103_Master')
        [string] $Database = "",

        [parameter(Mandatory=$True)] 
        [string] $SQLCredentialName = "", ## Your Credentials name (e.g 'DatabaseCred')

        [parameter(Mandatory=$False)]
        [int] $FragPercentage = 20, ## The minimum average % fragmentation of tables to include (e.g '20')

        [parameter(Mandatory=$False)]
        [int] $SqlServerPort = 1433, ## Your SQL Server Port (usually '1433')

        [parameter(Mandatory=$False)]
        [boolean] $RebuildOffline = $False, ## If the Rebuild should be carried out while the database is still accessible or not (use online to keep accessible)

        [parameter(Mandatory=$False)]
        [string] $Table ## Name of a single table that should be re-indexed only (e.g 'Items'). Leave empty for all tables.
    )

    Write-Output "Running Sitecore DB Maintenance Plan Workflow...`n`r"

    # Get the stored username and password from the Automation credential
    $SqlCredential = Get-AutomationPSCredential -Name $SQLCredentialName
    if ($SqlCredential -eq $null)
    {
        throw "Could not retrieve '$SQLCredentialName' credential asset. Check that you created this first in the Automation service."
    }
    else{
        Write-Output "Credential asset: '$SQLCredentialName' found, getting tables to defrag...`n`r"
        #output the tables found for indexing
        Write-Output "Fragmented Tables" 
        Write-Output "---------------------`n`r"
    }

    $SqlUsername = $SqlCredential.UserName 
    $SqlPass = $SqlCredential.GetNetworkCredential().Password

    $TableNames = Inlinescript {
        $db = $Using:Database
        $frag = $Using:FragPercentage

        # Define the connection to the SQL Database
        $Conn = New-Object System.Data.SqlClient.SqlConnection("Server=tcp:$using:SqlServer,$using:SqlServerPort;Database=$using:Database;User ID=$using:SqlUsername;Password=$using:SqlPass;Trusted_Connection=False;Encrypt=True;Connection Timeout=30;")

        # Open the SQL connection
        $Conn.Open()

        # SQL command to find tables and their average fragmentation
        $SQLCommandString = @"
        SELECT t.Name, MAX(avg_fragmentation_in_percent) MaxFragmentation
        FROM sys.dm_db_index_physical_stats (
                DB_ID(N'$db'),
                OBJECT_ID(0),
                NULL,
                NULL,
                NULL
            ) a
            JOIN sys.indexes b ON a.object_id = b.object_id AND a.index_id = b.index_id
            JOIN sys.tables t on t.object_id = a.object_id
        WHERE a.avg_fragmentation_in_percent >= $frag
        GROUP BY t.name;
"@
        
        # Return the tables with their corresponding average fragmentation
        $Cmd=new-object system.Data.SqlClient.SqlCommand($SQLCommandString, $Conn)
        $Cmd.CommandTimeout=120

        # Execute the SQL command
        $FragmentedTable=New-Object system.Data.DataSet
        $Da=New-Object system.Data.SqlClient.SqlDataAdapter($Cmd)
        [void]$Da.fill($FragmentedTable)
        $fragCount = 0

        # Return the table names that have high fragmentation
        ForEach ($FragTable in $FragmentedTable.Tables[0])
        {
            $fragCount++
            Write-Verbose "Table: $($FragTable.Item("Name")) - Max Fragmentation: $($FragTable.Item("MaxFragmentation"))" -Verbose
            
            $FragTable.Item("Name")
        }
        $Conn.Close()
        
        Write-Verbose "------------------------------------`n`r" -Verbose
        Write-Verbose "Total Fragmented Tables Found: $fragCount" -Verbose
    }

    # If a specific table was specified, then find this table if it needs to indexed, otherwise
    # set the TableNames to $null since we shouldn't process any other tables.
    If ($Table)
    {
        Write-Output "Single Table specified: $Table"
        If ($TableNames -contains $Table)
        {
            $TableNames = $Table
        }
        Else
        {
            # Remove other tables since only a specific table was specified.
            Write-Output "Table not found: $Table"
            $TableNames = $Null
        }
    }

    # Iterate through tables with high fragmentation and rebuild indexes
    ForEach ($TableName in $TableNames)
    {
    
      #create a workflow checkpoint incase the workflow is interrupted due to an db error etc. PowerShell Workflow uses the data in newest checkpoint to recover and resume the workflow.
      Write-Verbose "Creating checkpoint" -Verbose
      Checkpoint-Workflow
      Write-Output "Indexing Table: $TableName..."

      InlineScript {

        $SQLCommandString = @"
        EXEC('ALTER INDEX ALL ON $Using:TableName REBUILD with (ONLINE=ON)')
"@

        # Define the connection to the SQL Database
        $Conn = New-Object System.Data.SqlClient.SqlConnection("Server=tcp:$using:SqlServer,$using:SqlServerPort;Database=$using:Database;User ID=$using:SqlUsername;Password=$using:SqlPass;Trusted_Connection=False;Encrypt=True;Connection Timeout=30;")

        # Open the SQL connection
        $Conn.Open()

        # Define the SQL command to run. In this case we are getting the number of rows in the table
        $Cmd=new-object system.Data.SqlClient.SqlCommand($SQLCommandString, $Conn)
        # Set the Timeout to be less than 30 minutes since the job will get queued if > 30
        # Setting to 25 minutes to be safe.
        $Cmd.CommandTimeout=1500

        # Execute the SQL command
        Try 
        {
            $Ds=New-Object system.Data.DataSet
            $Da=New-Object system.Data.SqlClient.SqlDataAdapter($Cmd)
            [void]$Da.fill($Ds)
        }
        Catch
        {
            if (($_.Exception -match "offline") -and ($Using:RebuildOffline) )
            {
                Write-Output "Building table $Using:TableName offline"

                $SQLCommandString = @"
                EXEC('ALTER INDEX ALL ON $Using:TableName REBUILD')
"@

                # Define the SQL command to run. 
                $Cmd=new-object system.Data.SqlClient.SqlCommand($SQLCommandString, $Conn)
                # Set the Timeout to be less than 30 minutes since the job will get queued if > 30
                # Setting to 25 minutes to be safe.
                $Cmd.CommandTimeout=1500

                # Execute the SQL command
                $Ds=New-Object system.Data.DataSet
                $Da=New-Object system.Data.SqlClient.SqlDataAdapter($Cmd)
                [void]$Da.fill($Ds)
            }
            Else
            {
                # Will catch the exception here so other tables can be processed.
                Write-Error "Error, table $Using:TableName could not be indexed. Investigate indexing each index instead of the complete table $_"
             }
        }
        # Close the SQL connection
        $Conn.Close()
      }  
    }

    Write-Output "`n`r Finished Indexing all tables."
}