Why is space allocated for temporary tables not freed after deletion with a where clause?

Using CGTT (Created Global Temporary Table) you notice, that pages in the temporary table space are not reused after you have deleted all records (or only some) using a WHERE clause in the delete statement.
But if you delete all rows without a WHERE clause, the already allocated pages in the temporary table space are reused.

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time to get an answer from the API

Do you have an average of how much time does it take to the classifier to answer a question? because we did a loop with 50 question (50 API calls) and it took near a minute to finish. We have to figure out if the problem is in our side (communication) or in the NLC side (processing).

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Re-Train a Classifier not supported?

Is there a way to retrain a classifier that is already created?
if not, if we need 5 hr to train a classifier with 10.000 examples then if we add a new example will we need another 5 hours to train it again? At least I need to know if you are working on this important task

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