Escape variable in sqlcmd / Invoke-SqlCmd

Question

I am using powershell and using Invoke-SqlCmd. I am able to pass variables to SQL:

$variables = @( "MyVariable='hello'" )

Invoke-SqlCmd `
    -ServerInstance 'localhost' `
    -Database 'master' `
    -Username 'matthew' `
    -Password 'qwerty' `
    -Query 'SELECT $(MyVariable) AS foo' `
    -Variable $variables

This gives me back hello as expected. However, if I have a variable with a value containing an equals (=):

$variables = @("MyVariable='aGVsbG8NCg=='") # base64 encoded 'hello'

It gives me the following error:

The format used to define the new variable for Invoke-Sqlcmd cmdlet is invalid. Please use the 'var=value' format for defining a new variable.

I could not find any documentation on either sqlcmd or Invoke-SqlCmd on how I should escape values properly.

How do I escape variables sent to sqlcmd / Invoke-SqlCmd?

Answer 1

After investigating using some reflection on

C:\Program Files (x86)\Microsoft SQL Server\120\Tools\PowerShell\Modules\SQLPS\Microsoft.SqlServer.Management.PSSnapins.dll

Looking at ExecutionProcessor's constructor, the following lines reveal the problem that it will fail if there are more than one equals sign in the variable definition.

My recommendation for anyone else trying to use Invoke-SqlCmd is to save your time and sanity and just use the open source alternative Invoke-SqlCmd2 instead.

Microsoft, please fix.