[Revised] CSV -> SQL Express Code

Function IsScriptBlock
{
    param($value)

    if($value -and $value.GetType() -eq [System.Management.Automation.ScriptBlock])
    {
        return $true;
    }
    else
    {
        return $false;
    }
}

Function DatabaseHandler
{
    param($connection_string, $destination_table,$data_table,$timeout)
    $bulkCopy = New-Object Data.SqlClient.SqlBulkCopy($connection_string)
    $bulkCopy.DestinationTableName = $destination_table
    $bulkCopy.BulkCopyTimeout = $timeout
    $bulkCopy.WriteToServer($data_table)
}

function MakeColumn($column_name,$data_type)
{
    $column = New-Object System.Data.DataColumn
    $column.DataType = [System.Type]::GetType($data_type);
    $column.ColumnName = $column_name;

    return $column
}

function IntializeDataTable
{
    param($data_table,$column_data)

    foreach($column_specifier in $column_data)
    {
        $data_table.Columns.Add(
            (MakeColumn $column_specifier.name $column_specifier.data_type))
    }
}

Function CsvHandler
{
    param($data_table,$column_data)
    begin {
        Write-Host "Processing Started:" (Get-Date)
        $progress = 0
        $chunksize = 10000
    }
    process {

        $row = $data_table.NewRow()
        foreach($column_specifier in $column_data)
        {
            $name = $column_specifier.name
            if( $column_specifier.ContainsKey("function") -and ( IsScriptBlock $column_specifier.function ) )
            {
                $column_value = & $column_specifier.function $name $_
            }
            elseif ( $column_specifier.ContainsKey("fixed_value") )
            {
                $column_value = $column_specifier.fixed_value
            }
            else
            {
                $column_value = $_.$name
            }

            $row[$name] = $column_value
        }

        $data_table.Rows.Add($row)

        $progress++
        if($progress % $chunksize -eq 0)
        {
            Write-Host $chunksize "records processed"
        }
    }
    end {
        Write-Host "Processing Ended:" (Get-Date)
    }
}

Function PopulateDatabaseFromCsv
{
    param($csv,$column_data,$connection_string,$destination_table,$timeout=30)

    $data_table = New-Object System.Data.DataTable($destination_table)
    IntializeDataTable $data_table $column_data
    Import-Csv $csv | CsvHandler $data_table $column_data
    DatabaseHandler $connection_string $destination_table $data_table $timeout
}

// Sample Usage
$connectionString = "Data Source=.\SQLEXPRESS;AttachDbFilename=C:\TEMP\Maxmind.mdf;Integrated Security=True;User Instance=True"
$csv = "C:\TEMP\GeoIPCountryWhois.csv"
$destinationTable = 'geoip'
$columnData = @(
    @{ name = 'startip'; data_type = 'System.UInt32'; },
    @{ name = 'endip'; data_type = 'System.UInt32'; },
    @{ name = 'country_code'; data_type = 'System.String'; },
    @{ name = 'country'; data_type = 'System.String'; }
)
PopulateDatabaseFromCsv $csv $columnData $connectionString $destinationTable 200