CREATE TABLE place_filter (
    level TEXT,
    filter TEXT
);
-- this table must be initialized
INSERT INTO place_filter VALUES ('level_3', '%');

Then I wrote my first set-returning function, by trial-and-error.

CREATE OR REPLACE FUNCTION filtered_places() RETURNS SETOF places AS $$
DECLARE
    fl place_filter%ROWTYPE;
    pl places%ROWTYPE;
BEGIN
    SELECT * FROM place_filter INTO fl;
    FOR pl IN EXECUTE
        'SELECT * FROM places WHERE ' || QUOTE_IDENT(fl.level) ||
        ' LIKE ' || QUOTE_LITERAL(fl.filter) || ' OR place_id = 1'
    LOOP
        RETURN NEXT pl;
    END LOOP;
    RETURN;
END
$$ LANGUAGE plpgsql STABLE;

One of the nice things with such a function is that you can call it just the same way as you would do with a table or a view:

$handle = pg_query("SELECT place_id, get_place_name(place_id) AS place_name
                            FROM filtered_places() WHERE place_id > 0 ORDER BY place_name");

I haven’t written a PHP interface for the place filter yet; for now I just issue an "UPDATE place_filter SET level = 'level_3', filter = '%Solum';" from the psql prompt. Usually I do long runs of research within one parish, so I don’t have to “change the filter” often.

I've been continuing hacking on pgTAP in order to add a lot more schema-testing functionality and a few other niceties. But back when I started the project, I using it to write tests for CITEXT, which was great for my sanity as I developed it, but proved a bit controversial. In a pgsql-hackers post, Tom Lane wrote:

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My own experience with Postgres has been incredibly positive and welcoming. I always wish that I had more time to contribute.

I did find a little time this weekend to upgrade the PostgreSQL User Group site to the latest supported version of Drupal. We’re still on version 5.x, and hopefully I’ll be able to upgrade that to version 6.x soon. We’ve had a few problems with spammers, but I added a CAPTCHA that I hope isn’t too annoying for everyone.

If you have ideas for how to display the information on the PUGs site in a better way, please get in touch. I have a couple things I’d like to add soon - like a map of locations, and a better preview of recently posted articles.

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If you have been invited to join the Embarcadero Weaver Beta Test and you’re an owner of PostgresDAC license, you’ve got an opportunity for incredible PostgresDAC Licenses and Renewals discount for you and your friends or colleagues.

Details…

It seems changing the Number of Buffer Partitions for this workload does not have any impact. My dataset for this iGen benchmark is pretty small and should easily fit under 2GB size and hence may not be stressing the buffer partitions too much to warrant bigger number. The patch still helps to get good healthy 4-6% gain in peak values.

Decided to read PostgreSQL 8.4 Release notes before going to sleep and was pleasantly surprised. The fact of ALTER statements mess (which I described in my post) is now fixed:

Modify the ALTER TABLE syntax to allow all reasonable combinations for tables, indexes, sequences, and views (Tom)

This change allows the following new syntaxes:

• ALTER SEQUENCE OWNER TO
• ALTER VIEW ALTER COLUMN SET/DROP DEFAULT
• ALTER VIEW OWNER TO
• ALTER VIEW SET SCHEMA

There is no actual new functionality here, but formerly you had to say ALTER TABLE to do these things, which was confusing.

Cool! Way to go!