select ... for update in plpgsql

Hi,

I have a question about 'select ... for update';
according to the docs,
clause 'for update' will lock selected rows,
I believe it should be put into a
begin;
select ... for update;
update ...;
end;
block.

however, if I use it in a plpgsql function,
do I need another pair of begin...end?
or say begin...end in plpgsql can lock chosen rows until
updated ALL ROWS?
if not, do you have any suggestion?

Jie LIANG

St. Bernard Software

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Suite 100, San Diego, CA 92121
Office:(858)320-4873

jliang(at)ipinc(dot)com
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