It is. But why do you care? You either have the correctness that
NUMERIC gives, or you don't.
I suspect it's still useful to know what order of magnitude slower it
is. After all if it is 1000x slower (not saying it is), some people may
decide it's not worth it or roll their own.
Any hints/gotchas for/when doing such performance tests?
forum_bench=> CREATE TEMPORARY TABLE test AS SELECT a::FLOAT AS f,
a::NUMERIC AS n, a::INTEGER AS i, a::BIGINT AS b FROM
generate_series( 1,100000 ) AS a;
SELECT
Temps : 1169,125 ms
forum_bench=> SELECT sum(i) FROM test;
Temps : 46,589 ms
forum_bench=> SELECT sum(b) FROM test;
Temps : 157,018 ms
forum_bench=> SELECT sum(f) FROM test;
Temps : 63,865 ms
forum_bench=> SELECT sum(n) FROM test;
Temps : 124,816 ms
SELECT * FROM test ORDER BY i LIMIT 1; SELECT * FROM test ORDER BY b LIMIT
1; SELECT * FROM test ORDER BY f LIMIT 1; SELECT * FROM test ORDER BY n
LIMIT 1;
Temps : 68,996 ms
Temps : 68,917 ms
Temps : 62,321 ms
Temps : 71,880 ms
BEGIN; CREATE INDEX test_i ON test(i); CREATE INDEX test_b ON test(b);
CREATE INDEX test_f ON test(f); CREATE INDEX test_n ON test(n); ROLLBACK;
CREATE INDEX
Temps : 102,901 ms
CREATE INDEX
Temps : 123,406 ms
CREATE INDEX
Temps : 105,255 ms
CREATE INDEX
Temps : 134,468 ms
