pgsql: Add comments on avoid reuse of parse-time snapshot - Mailing list pgsql-committers

Add comments on avoid reuse of parse-time snapshot

Apparently, reusing the parse-time query snapshot for later steps
(execution) is a frequently considered optimization ... but it doesn't
work, for reasons discovered in thread [1].  Adding some comments about
why it doesn't really work can relieve some future hackers from wasting
time reimplementing it again.

[1] https://postgr.es/m/flat/5075D8DF.6050500@fuzzy.cz

Author: Michail Nikolaev
Discussion: https://postgr.es/m/CANtu0ogp6cTvMJObXP8n=k+JtqxY1iT9UV5MbGCpjjPa5crCiw@mail.gmail.com

Branch
------
master

Details
-------
https://git.postgresql.org/pg/commitdiff/db989184cda7f4aa1ff764cca96142029e7e093b

Modified Files
--------------
src/backend/tcop/postgres.c | 11 ++++++++++-
1 file changed, 10 insertions(+), 1 deletion(-)