On 05/04/2017 06:22 PM, Andrew Dunstan wrote:
I wrote this query:select (json_populate_record(null::mytype, myjson)).* from mytable; It turned out that this was an order of magnitude faster: with r as ( select json_populate_record(null::mytype, myjson) as x from mytable ) select (x).* from r;
I do not know the planner that well, but I imagined that when we remove the optimization fence that one would be evaluated similar to if it had been a lateral join, i.e. there would be no extra function calls in this case after removing the fence.
Andreas -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
