if sagemaker dataset gets a new version automatically, does the model automatically rebuild?

When a SageMaker Canvas dataset is automatically updated, the model does not automatically rebuild with the new data. Each dataset update creates a new version of your dataset, but you would need to manually rebuild your model using this latest dataset version.

However, SageMaker Canvas does offer automation capabilities that can help streamline your workflow. While models don't automatically rebuild, you can set up automatic batch predictions that run whenever your dataset is updated. This means that if you have an existing model and your dataset receives an update, you can configure the system to automatically generate new predictions using your current model on the updated data.

You can set up a workflow where:

1. Your dataset automatically updates on a schedule (up to 20 automatic configurations are allowed)
2. Batch predictions automatically run using your existing model whenever the dataset updates

These automations only run while you're logged into the Canvas application and pause when you log out. To manage these automations, you can use the ML Ops section in Canvas, where you can view, edit, or delete your automation configurations.

While this doesn't solve the need to manually rebuild models with fresh data, it does provide some level of automation for generating predictions with your existing model on newly updated data.
Sources
Update a dataset - Amazon SageMaker
How to manage automations - Amazon SageMaker
Edit your automatic dataset update configuration - Amazon SageMaker