On 2021-Nov-24, Robert Haas wrote:
> Hmm. I think in my model an item and an item pointer and a line
> pointer are all the same thing, but a TID is different. When I talk
> about a TID, I mean the location of an item pointer, not its contents.
> So a TID is what tells me that I want block 5 and the 4th slot in the
> item pointer array. The item pointer tells me that the associate tuple
> is at a certain position in the page and has a certain length.
OK, but you can have item pointers that don't have any item.
LP_REDIRECT, LP_DEAD, LP_UNUSED item pointers don't have items.
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Álvaro Herrera Valdivia, Chile — https://www.EnterpriseDB.com/
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