On 8/23/24 12:02, Rafia Sabih wrote:
On the other hand, this got me thinking about the purpose of this space information. If we want to understand that there's still some space for the tuples in a page, then using PageGetExactFreeSpace is not doing justice in case of heap page, because we will not be able to add any more tuples there if there are already MaxHeapTuplesPerPage tuples there.
We won't be able to add, but we will be able to update a tuple in this page. It's hard to test, because I can't fit more than 226 tuples on a single page, while MaxHeapTuplesPerPage = 291 on my machine :-)
In any case, IMVHO, pgstattuple shouldn't answer to the question "can I add more tuples?". The goal is for educational, introspection or debugging purposes, and we want the exact amount of free space.
Best regards, Frédéric
