SQL Azure backup on-prem using Powershell - azure

Question

I have this Powershell script I am trying to run, to do me a 'bacpac' file from an Azure tenancy database, to on-prem (local folder).
# Load SMO Assembly
[System.Reflection.Assembly]::LoadWithPartialName("Microsoft.SqlServer.SMO") | Out-Null
# Define the source database
$sourceServer = "myserver-sql-server"
$sourceDB = "mydb-sql-db"
# Define the target file
$targetFile = "c:\temp\mydb.bacpac"
# Connect to the source database
$sourceServer = New-Object Microsoft.SqlServer.Management.Smo.Server $sourceServer
$sourceDB = $sourceServer.Databases[$sourceDB]
# Export the database to the target file
$sourceDB.ExportBacpac($targetFile)
The error I am getting is on the last line...
You cannot call a method on a null-valued expression. At line:2 char:1
$sourceDB.ExportBacpac($targetFile)
+ CategoryInfo : InvalidOperation: (:) [], RuntimeException
+ FullyQualifiedErrorId : InvokeMethodOnNull
The variables have values. Am I missing a parameter calling 'ExportBacPac'?

Answer 1

This script worked...
Function Get-Bacpacs {
Param(
[string]$location
, [string]$server
, [string]$smolibrary
, [string]$daclibrary
, [string]$username
, [string]$password
)
Process
{
$dt = Get-Date -uFormat "%Y%m%d"
Add-Type -Path $smolibrary
$scon = "Data Source=$server.database.windows.net;Initial Catalog=master;User ID=$username;Password=$password;"
$servercon = New-Object Microsoft.SqlServer.Management.Common.ServerConnection
$servercon.ConnectionString = $scon
$srv = New-Object Microsoft.SqlServer.Management.SMO.Server($servercon)
foreach ($db in $srv.Databases | Where-Object {$_.Name -ne "master"})
{
$database = $db.Name
$bak_scon = "Data Source=$server.database.windows.net;Initial Catalog=$database;Connection Timeout=0;User ID=$username;Password=$password;"
if (!(Test-Path $location))
{
New-Item $location -ItemType Directory
}
$outfile = $location + $database + "_" + $dt + ".bacpac"
Add-Type -Path $daclibrary
$d_exbac = New-Object Microsoft.SqlServer.Dac.DacServices $bak_scon
try
{
$d_exbac.ExportBacpac($outfile, $database)
}
catch
{
Write-Warning $_
### Other alerting can go here
}
}
}
}
### This makes it easier for us who don't have really long screens! Location may vary.
$smo = "C:\Program Files (x86)\Microsoft SQL Server\110\SDK\Assemblies\Microsoft.SqlServer.Smo.dll"
$dac = "C:\Program Files (x86)\Microsoft SQL Server\110\DAC\bin\Microsoft.SqlServer.Dac.dll"
Get-Bacpacs -location "" -server "" -smolibrary $smo -daclibrary $dac -username "" -password ""