Hello,
When implementing a GiST consistent function I found the need to cache pre-processed query across invocations.
I am not sure if it is safe to do (or I need to perform some steps to make sure cached info is not leaked between rescans).
The comment in gistrescan says:
/*
* If this isn't the first time through, preserve the fn_extra
* pointers, so that if the consistentFns are using them to cache
* data, that data is not leaked across a rescan.
*/
which seems to me self-contradictory as fn_extra is preserved between rescans (so leaks are indeed possible).
Am I missing something?
Thanks,
Michal