Peter Eisentraut wrote:
> Rob wrote:
> > But I think there is room to go further, I don't see any reason why
> > that default install can't include example DBs,
>
> One reason is that a useful example database would likely have a
> download footprint of 10 MB or more. Having this in the default
> download would not be appreciated by many people. Of course having
> some example database available at all would be a good idea, but then
> as a separate download.
Here is a little psql script I wrote to populate a table with random
data.
--
Bruce Momjian | http://candle.pha.pa.us
[EMAIL PROTECTED] | (610) 359-1001
+ If your life is a hard drive, | 13 Roberts Road
+ Christ can be your backup. | Newtown Square, Pennsylvania 19073
\set ECHO all
\timing
DROP TABLE perftest;
CREATE TABLE perftest (col text);
-- prime table with one row
INSERT INTO perftest VALUES ('0.364461265208414');
-- continously double the table size
INSERT INTO perftest SELECT random()::text FROM perftest;
INSERT INTO perftest SELECT random()::text FROM perftest;
INSERT INTO perftest SELECT random()::text FROM perftest;
INSERT INTO perftest SELECT random()::text FROM perftest;
INSERT INTO perftest SELECT random()::text FROM perftest;
INSERT INTO perftest SELECT random()::text FROM perftest;
INSERT INTO perftest SELECT random()::text FROM perftest;
INSERT INTO perftest SELECT random()::text FROM perftest;
INSERT INTO perftest SELECT random()::text FROM perftest;
INSERT INTO perftest SELECT random()::text FROM perftest;
INSERT INTO perftest SELECT random()::text FROM perftest;
INSERT INTO perftest SELECT random()::text FROM perftest;
INSERT INTO perftest SELECT random()::text FROM perftest;
INSERT INTO perftest SELECT random()::text FROM perftest;
-- insert a constant in the middle of the table, for use later
INSERT INTO perftest VALUES ('0.608254158221304');
INSERT INTO perftest SELECT random()::text FROM perftest;
-- 32770 rows
-- vacuum, create index
VACUUM ANALYZE perftest;
CREATE INDEX i_perftest ON perftest (col);
-- reduce chance of checkpoint during tests
CHECKPOINT;
-- turn on logging
SET log_duration = TRUE;
SET client_min_messages = 'log';
-- run normal and prepared queries
SELECT col FROM perftest WHERE col = '0.608254158221304';
SELECT col FROM perftest WHERE col = '0.608254158221304';
SELECT col FROM perftest WHERE col = '0.608254158221304';
SELECT col FROM perftest WHERE col = '0.608254158221304';
SELECT col FROM perftest WHERE col = '0.608254158221304';
PREPARE perftest_prep (text) AS SELECT col FROM perftest WHERE col = $1;
EXECUTE perftest_prep ('0.608254158221304');
EXECUTE perftest_prep ('0.608254158221304');
EXECUTE perftest_prep ('0.608254158221304');
EXECUTE perftest_prep ('0.608254158221304');
EXECUTE perftest_prep ('0.608254158221304');
-- first time the entire statement
SET log_statement_stats = TRUE;
-- run normal and prepared queries
SELECT col FROM perftest WHERE col = '0.608254158221304';
SELECT col FROM perftest WHERE col = '0.608254158221304';
SELECT col FROM perftest WHERE col = '0.608254158221304';
SELECT col FROM perftest WHERE col = '0.608254158221304';
SELECT col FROM perftest WHERE col = '0.608254158221304';
PREPARE perftest_prep (text) AS SELECT col FROM perftest WHERE col = $1;
EXECUTE perftest_prep ('0.608254158221304');
EXECUTE perftest_prep ('0.608254158221304');
EXECUTE perftest_prep ('0.608254158221304');
EXECUTE perftest_prep ('0.608254158221304');
EXECUTE perftest_prep ('0.608254158221304');
-- now log each query stage
SET log_statement_stats = FALSE;
SET log_parser_stats = TRUE;
SET log_planner_stats = TRUE;
SET log_executor_stats = TRUE;
-- run normal and prepared queries
SELECT col FROM perftest WHERE col = '0.608254158221304';
SELECT col FROM perftest WHERE col = '0.608254158221304';
SELECT col FROM perftest WHERE col = '0.608254158221304';
SELECT col FROM perftest WHERE col = '0.608254158221304';
SELECT col FROM perftest WHERE col = '0.608254158221304';
EXECUTE perftest_prep ('0.608254158221304');
EXECUTE perftest_prep ('0.608254158221304');
EXECUTE perftest_prep ('0.608254158221304');
EXECUTE perftest_prep ('0.608254158221304');
EXECUTE perftest_prep ('0.608254158221304');
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