This extra code you're seeing during "start execution" is Dataform's way of ensuring the environment is properly set up before running your SQL. To put it simply, it's taking care of schema creation if it doesn't already exist. This is a built-in feature to prevent errors if the target schema is missing. This is a best practice for production deployments as it prevents failures if the schema doesn't already exist.

You don't actually need to remove this generated code. It's crucial for robust deployments.