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Here’s the question that Gwen poses:

What happens when you add and remove a column from a table in Postgres 2000 times?

I couldn’t come up with any good guesses.

The surprising answer is that PostgreSQL 1) has a hard limit of 1600 columns on any given table and 2) that removes columns are effectively soft-deleted. This means that each column you add to a table, regardless of whether it is later deleted, will contribute to that hard limit.

If you somehow run into this limit in a real-world database deployment (unlikely), you’ll have to swap everything into a new table to get around it.