About dtype changes to String automatically even defined as GUID in Variable Library

Krrish12 — Tue, 19 May 2026 11:46:37 GMT

Hello,

I had created a Variable library with guid type , but when I am using that same variable in pipeline dynamically , it is being used as String. Basically , I have inserted my connection string in variable of type GUID , which when I am trying to access dynamically in connections , it is giving me below error
Failed to resolve the connection.

Error Message: {
"hasFirewallBypassToken": false,
"errorResponse": {
"error": {
"code": "400",
"message": "Failed to resolve connection 'pipeline().libraryVariables[\n concat('WorkspaceVariables_', pipeline().parameters.p_connection_name, '_connection')\n]\n' referenced in activity run '343d1e31-6125-44b4-bf17-4d28a3cf4078'. ErrorCode: 'InvalidExternalReferenceConnection'. ErrorMessage: 'Invalid datasourceObjectId: pipeline().libraryVariables[\n concat('WorkspaceVariables_', pipeline().parameters.p_connection_name, '_connection')\n]\n passed. It should be a valid Guid.'."
}
}
}

Below are screenshots

Re: About dtype changes to String automatically even defined as GUID in Variable Library

v-echaithra — Wed, 20 May 2026 05:46:09 GMT

Hi @Krrish12 ,

Thanks for using Fabric Community.

Currently, parameterization support for connections is not available in Fabric Data Factory. However, this capability is expected in future releases. You can follow the Fabric roadmap: Microsoft Fabric Roadmap for upcoming enhancements.

As a workaround, instead of dynamically resolving the connection GUID through libraryVariables, you can consider the following approaches:

Use If/Switch activities and assign static connections.
Store the connection GUID in a pipeline parameter and pass the actual GUID value directly.

Best Regards.

topic Re: About dtype changes to String automatically even defined as GUID in Variable Library in Data Engineering

About dtype changes to String automatically even defined as GUID in Variable Library

Re: About dtype changes to String automatically even defined as GUID in Variable Library