On 2021-Nov-24, Alvaro Herrera wrote: > 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.
Sorry to reply to myself, but I realized that I forgot to return to the main point of this thread. If we agree that "an LP_DEAD item pointer does not point to any item" (an assertion that gives a precise meaning to both those terms), then a patch that renames "tuples" to "items" is not doing anything useful IMO, because those two terms are synonyms. Now maybe Peter doesn't agree with the definitions I suggest, in which case I would like to know what his definitions are. -- Álvaro Herrera PostgreSQL Developer — https://www.EnterpriseDB.com/ "How strange it is to find the words "Perl" and "saner" in such close proximity, with no apparent sense of irony. I doubt that Larry himself could have managed it." (ncm, http://lwn.net/Articles/174769/)
