1. Do we need to consider when to delete the extension hook or it's not necessary?
As the destroy function _PG_fini doesn't work, I cannot find a good place to reset to hook gracefully.
I tested the drop language plpythonu statement which will not remove the python shared library in the current session,
So it seems to be safe to leave the cancel_handler_hook not be reset.
How about other extensions, for example plr. Does the "drop extension" statement will not remove the loaded shared library in the process either?
-- Another idea is to register the hook at the beginning of plpython_call_handler and unregister the hook at the end of plpython_call_handler.
2. Do we need to use explicit hook list(List *cancel_hook_list) instead of implicit cancel_hook(which relies on the extension to link the cancel_hook inside their code
e.g. prev_hook = cancel_hook; cancel_hook=my_hook; void my_hook(){mywork(); (*prev_hook)();} )?
I didn't find any explicit hook list in PG code base, is that a good practice?
-- Hubert
On Mon, May 14, 2018 at 6:40 PM, Heikki Linnakangas <hlinnaka@iki.fi> wrote:
On 14/05/18 10:56, Hubert Zhang wrote:
For nested SPI case, one option is to turn off the bool variable when entering the SPI function(PLy_spi_prepare, PLy_spi_execute, PLy_cursor etc.) and turn on the bool variable again when exiting the SPI function.
