If you look into the results, you will see that they are able to execute 5x TPC-H queries in ~200ms (total). The dataset is not large it is rather small (10GB) but nonetheless, you wouldn't be able to run 5 queries in such a small amount of time if you had to analyze the workload, generate the code, build indices, start the agents/engine and retrieve the results. I didn't read the whole paper but this is why I think your understanding is wrong.
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If you look into the results, you will see that they are able to execute 5x TPC-H queries in ~200ms (total). The dataset is not large it is rather small (10GB) but nonetheless, you wouldn't be able to run 5 queries in such a small amount of time if you had to analyze the workload, generate the code, build indices, start the agents/engine and retrieve the results. I didn't read the whole paper but this is why I think your understanding is wrong.