Hi there,
I'm a bit surprised how bad could be plan for unused table.
I had to cancel second query :)
tp=# explain analyze select tp_rewrite_substitute(query,
'select p.name_tsquery, p.name_alias_tsquery from place p')
from to_tsquery('new&york&hotel') as query;
y; QUERY PLAN
---------------------------------------------------------------------------------------------------------------
FunctionScan on query (cost=0.00..15.00 rows=1000 width=32) (actual time=3801.069..3801.071 rows=1 loops=1) Total
runtime:3801.107 ms
(2 rows)
tp=# explain analyze select tp_rewrite_substitute(query,
'select p.name_tsquery, p.name_alias_tsquery from place p')
from place, to_tsquery('new&york&hotel') as query; ^^^^^
Here is plan without analyze:
tp=# explain select tp_rewrite_substitute(query,
'select p.name_tsquery, p.name_alias_tsquery from place p')
from place, to_tsquery('new&york&hotel') as query; QUERY PLAN
--------------------------------------------------------------------------- Nested Loop (cost=13.50..44280620.90
rows=1964340000width=32) -> Seq Scan on place (cost=0.00..82957.40 rows=1964340 width=0) -> Materialize
(cost=13.50..23.50rows=1000 width=32) -> Function Scan on query (cost=0.00..12.50 rows=1000 width=32)
(4 rows)
The only difference is unused table 'place' in FROM-clause. I typed in by
mistake, but I think optimizer could figure out not to take into account
this table.
Regards, Oleg
_____________________________________________________________
Oleg Bartunov, sci.researcher, hostmaster of AstroNet,
Sternberg Astronomical Institute, Moscow University (Russia)
Internet: oleg@sai.msu.su, http://www.sai.msu.su/~megera/
phone: +007(095)939-16-83, +007(095)939-23-83
