do queries from strings in pgplsql

Hi list,

I'm just added to the list and I'm not sure whether the following is a
FAQ or not possible. Anyway, here it goes:
       Is it possible to execute a query stored into a string?

I mean, something like:

function test(text) as returns opaque as '
declare v_weekday alias for $1; s_qry text; rec record;
begin s_qry = ''select field1,field2, '' || v_weekday || '' from t_diary''; for rec in exec_sql(s_qry)loop
--                 ^ that is what I'm looking for...
--        [do what is needed] end loop;
end;
' language 'plpgsql';

Thanks in advance,
Virgilio Sanz

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Virgilio Sanz               vsanz@el-mundo.net virgilio.sanz@el-mundo.es
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