postgres for 循环

1.

do $$
declare
a integer := 1;
beginwhile a < 1000000 loop
--循环体内容....--变量改变+1a= a+1;end loop;end $$;

2.
 

do
$do$
declarei int;
begin
for  i in 1..3000000
loopINSERT INTO USAGE_RECORD (id, quantity)
VALUES ( uuid_generate_v4(),  500+i, );end loop;
end;
$do$;