BIML Studio vs Visual Studio

We are creating a new data warehouse using SSIS and are looking at BIML Studio. I know that for BIML Express I need Visual Studio, but for BIML Studio it seems that we don't even need Visual Studio if we develop our entire ETL with BIML Studio. Is this correct or do I still need Visual Studio in some way?

Standard consulting answer: "It depends"

Your BimlStudio workflow is probably going to be a few BimlScript files that contain your core logic. And then there's gonna be the generated artifacts. As an example, here's shot of the Logical view of my current Biml project. It's a large and still growing "export procs to fixed width files" solution for a client.

Since I need to write to a flat file, that means each package needs a Flat File Connection Manager and a Flat File Connection Manager needs a Flat File Format definition. So, 1 logical entity requires 3 Biml artifacts (at least for how I'm building it)

What you see in the BimlScripts and Connections folder are what run the project (plus the custom metadata repository aka "one big table").

The black circle next to 01_FFF.biml means that's a "live" Biml so every time I make a change to my metadata or the underlying file, whoosh out comes 45 File Format entries (project view)

All of this is great but eventually, I need to translate what's in my Integration Services node (1 project, 45 Packages) into a deliverable.

What's your deliverable?

Right clicking on the project gives me 3 options: Build, Build & Run, Build and & Open in SSDT

• Build - this results in a .ispac file being created. That's the quantum for pushing a project deployment model into the SSISDB
• Build & Run - Honestly, I don't know what this option does. I should check the book https://link.springer.com/book/10.1007/978-1-4842-3135-7
• Build & Open in SSDT - This results in everything you need to interact with the project in Visual Studio (a .dtproj file, Project.params, any Project level .conmgr files and all the associated .dtsx files)

When would I need Visual Studio?

Debugging. I'm pretty good at this stuff but even I miss some settings for things I don't have solid patterns for. For example, this project is using Fixed Width File Formats and in early iterations, I was getting defects open as the files weren't correct because the default file encoding was for Unicode, despite each individual column being defined as DT_STR (non-unicode). Little stuff like that is much easier to find and resolve and fix back in BimlStudio. Otherwise, you're trying to debug the results of a package execution but if you knew you had the wrong pattern, you wouldn't have built the bug into your pattern.