Re: Schema variables - new implementation for Postgres 15
От | Julien Rouhaud |
---|---|
Тема | Re: Schema variables - new implementation for Postgres 15 |
Дата | |
Msg-id | 20221104141713.4y3dpmlmp73zkwzb@jrouhaud обсуждение исходный текст |
Ответ на | Re: Schema variables - new implementation for Postgres 15 (Dmitry Dolgov <9erthalion6@gmail.com>) |
Список | pgsql-hackers |
Hi, On Fri, Nov 04, 2022 at 03:07:48PM +0100, Dmitry Dolgov wrote: > > On Fri, Nov 04, 2022 at 05:58:06AM +0100, Pavel Stehule wrote: > > Hi > > > > fix clang warning > > I've stumbled upon something that looks weird to me (inspired by the > example from tests): > > =# create variable v2 as int; > =# let v2 = 3; > =# create view vv2 as select coalesce(v2, 0) + 1000 as result > > =# select * from vv2; > result > -------- > 1003 > > =# set force_parallel_mode to on; > =# select * from vv2; > result > -------- > 1000 > > In the second select the actual work is done from a worker backend. > Since values of session variables are stored in the backend local > memory, it's not being shared with the worker and the value is not found > in the hash map. Does this suppose to be like that? There's code to serialize and restore all used variables for parallel workers (see code about PARAM_VARIABLE and queryDesc->num_session_variables / queryDesc->plannedstmt->sessionVariables). I haven't reviewed that part yet, but it's supposed to be working. Blind guess would be that it's missing something in expression walker.
В списке pgsql-hackers по дате отправления: