Which of the following HubL and HubDB behaviors should be avoided if possible?

Making multiple requests to the same HubDB table within a single template should be avoided because each request incurs overhead, increasing page load time and consuming more resources. It's more efficient to make a single request for the necessary data and then process or filter that data using HubL within the template. Using a filter query to reduce data returned is good practice as it minimizes the data transferred. The reject attribute filter is also an efficient way to refine data subsets after an initial request. Using loops to access data in multi-select columns is a standard and necessary practice for handling such data structures.