select ... for update

> Hi,

How can I use select ... for update to update limit to update what I
select??
somewhat like:
select url,id from mytable for update order by priority,id limit 5;
I want update the id in above return like:
update mytable set allocatedto='whatever' where id in above return set.
Could I do it in one stmt.
And what is class_name in following:
SELECT [ ALL | DISTINCT [ ON ( expression [, ...] ) ] ]
expression [ AS name ] [, ...]
[ INTO [ TEMPORARY | TEMP ] [ TABLE ] new_table ]
[ FROM table [ alias ] [, ...] ]
[ WHERE condition ]
[ GROUP BY column [, ...] ]
[ HAVING condition [, ...] ]
[ { UNION [ ALL ] | INTERSECT | EXCEPT } select ]
[ ORDER BY column [ ASC | DESC | USING operator ] [, ...] ]
[ FOR UPDATE [ OF class_name [, ...] ] ]
LIMIT { count | ALL } [ { OFFSET | , } start ]
can any one give me a example??

--
Jie LIANG

Internet Products Inc.

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jliang(at)ipinc(dot)com
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