GistPageSetDeleted() sets pd_lower when deleting a page, and sets the
page contents to a GISTDeletedPageContents. Avoid treating deleted GiST
pages as regular slotted pages within pageinspect.
Oversight in commit 756ab291.
Author: Andrey Borodin <x4mmm@yandex-team.ru>
Per Coverity. BuildIndexValueDescription() cannot actually return NULL in
this instance, because it only returns NULL if the user doesn't have the
required privileges, and this function can only be used by superuser. But
better safe than sorry.
The gist_page_items() function opened the index relation on first call and
closed it on the last call. But there's no guarantee that the function is
run to completion, leading to a relcache leak and warning at the end of
the transaction. To fix, refactor the function to return all the rows in
one call, as a tuplestore.
Reported-by: Tom Lane
Discussion: https://www.postgresql.org/message-id/234863.1610916631%40sss.pgh.pa.us
Peter Geoghegan
Heikki Linnakangas