Hi
I tested the following:
CREATE TABLE t1
(
id serial NOT NULL,
a character varying(125),
a_tsvector tsvector,
CONSTRAINT t1_pkey PRIMARY KEY (id)
);
INSERT INTO t1 (a, a_tsvector)
VALUES ('o,p,f,j,z,j',
to_tsvector('o,p,f,j,z,j');
rawi only4...@web.de writes:
And querying: FTS with prefix matching:
SELECT count(a)
FROM t1
WHERE a_tsvector @@ to_tsquery('aaa:* b:* c:* d:*')
(RESULT: count: 619)
Total query runtime: 21266 ms.
FWIW, I get fairly decent performance for cases like this in HEAD
(at least with a GIN
Tom Lane-2 wrote
FWIW, I get fairly decent performance for cases like this in HEAD
(at least with a GIN index; GIST seems much less able to do well with
short prefixes). What PG version are you testing?
Thank you Tom,
I'm testing on PG 9.1 on UbuntuServer 12.10, 64bit
I'll update to 9.2 the
Tom Lane-2 wrote
FWIW, I get fairly decent performance for cases like this in HEAD
(at least with a GIN index; GIST seems much less able to do well with
short prefixes).
Short or long prefixes seem to be equaly unfavorable. Even with the full
length of the words, but queried as prefix I get a
Is it valid to specify a SELECT statement as part of a JOIN clause?
For example:
SELECT table1.f1, table1.f2 FROM table1
INNER JOIN
(SELECT table2.f1, table2.f2 FROM table2) table_aux ON table1.f1 =
table_aux.f1
Respectfully,
Jorge Maldonado
It works.
Also consider views.
Just used this on a my db:
SELECT * FROM tblcus_customer
INNER JOIN
( SELECT * FROM tblcus_customer_status WHERE status_id 0) AS b
ON tblcus_customer.status = b.status_id
You can even join with a function result.
Regards,
Luca.
2013/6/14 JORGE MALDONADO
