Selecting random element?

Does anyone have a way to select a random element without doing a complete select on the database first?

For example, right now I would have to (under PHP3):

$rs = pg_exec($db,"SELECT * FROM database");
$rec = pg_fetch_object($rs,rand(1,pg_numrows($rs)));

It would be a lot easier to just do a

$rs = pg_exec($db,"SELECT * from database RANDOM")

or some such where it would select a random row.

_____
Justin Long
Network for Strategic Missions
1732 South Park Court, Chesapeake, VA 23320
Ofc 757-420-4500, Fax 757-226-5006, Email justinlong(at)strategicnetwork(dot)org
Never retreat. Never surrender. Never cut a deal with a dragon.
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