Re: Interesting question

* Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> [010518 22:39]:
> Larry Rosenman <ler(at)lerctr(dot)org> writes:
> > CREATE FUNCTION "nowminus" (interval) RETURNS timestamp with time zone AS 'SELECT now() - $1;' LANGUAGE 'sql';
>
> Right idea, but you need to mark it iscachable.
Aha:

Same query, with nowminus marked iscachable:
NOTICE: QUERY PLAN:

Sort (cost=513.69..513.69 rows=447 width=120)
-> Index Scan using start_index, end_index on attack_db (cost=0.00..494.01 rows=447 width=120)
SubPlan
-> Seq Scan on exempt_ips (cost=0.00..1.04 rows=4 width=12)
-> Seq Scan on exempt_ips (cost=0.00..1.04 rows=4 width=12)

EXPLAIN
>
> regards, tom lane

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Larry Rosenman http://www.lerctr.org/~ler
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