Defining SQLCMD variables in the project prevents them from being set via environment variables

[MrazqRuby]

It seems to me that defining the <SqlCmdVariable> ... </SqlCmdVariable> is actually worse than not defining it.

I am building a .dacpac with this SDK with a Post-Deploy script that uses variables like this:

IF (1 = ISNULL($(SQLCMD_DEPLOY_CONFIGS), 0))
BEGIN
# ...
END

I am not defining <SqlCmdVariable> ... </SqlCmdVariable> anywhere.

1. Running sqlpackage.exe /a:Publish ... in a container where the SQLCMD_DEPLOY_CONFIGS environment variable is defined results in the value from the environment variable being replaced in the script.
2. Running sqlpackage.exe /a:Publish ... /v:SQLCMD_DEPLOY_CONFIGS=0 also works, although it prints "The following SqlCmd variables are not defined in the target scripts: SQLCMD_DEPLOY_CONFIGS."

BUT

If I go and now define:

<SqlCmdVariable Include="SQLCMD_DEPLOY_CONFIGS">
		<!--Defines whether configuration scripts should be deployed: 0 - No, 1 - Yes-->
	<DefaultValue>$(SQLCMD_DEPLOY_CONFIGS)</DefaultValue>
	<Value>$(SQLCMD_DEPLOY_CONFIGS)</Value>
</SqlCmdVariable>

then the approach with the environment variable (1) no longer works. So to me it seems that it is worse to define the sqlcmd vars?