Question

I d like to set up a query with a loop inside a for loop using plpgsql. I m writing it like :

FOR ___ IN value..value BY 1 LOOP
  LOOP
    statement
    EXIT WHEN ...
  END LOOP;
END LOOP;

它给我留下了第二处“失眠”的yn误,因此,我怀疑这种 lo在一旁的可行性。

我希望我明确表示。

Answer 1

我看不出有任何问题在 plgpgsql 后gresql 11.10中登出一条nes:

DO $$
DECLARE 
    i integer;
    j integer;
BEGIN
FOR i IN 1..2 LOOP
    FOR j IN 10..12 LOOP
    -- i will take on the values 1,2,3,4,5,6,7,8,9,10 within the loop
    RAISE NOTICE  loop % % ,i,j;
    END LOOP;
END LOOP;
END$$;

I see expected output:

loop 1 10
loop 1 11
loop 1 12
loop 2 10
loop 2 11
loop 2 12

Answer 2

因此,我看到的最初问题是,你的反响是围绕一系列“价值”。

审视这一法典,范围应当是2种不同的价值观。首先是这样。

do $$
begin 
  for counter in 1..6 by 2 loop
    raise notice  counter: % , counter;
  end loop;
end; $$

Answer 3

<>>,载于。 * E/CN.6/2009/1。

DO $$
DECLARE
  num INT := 0;
BEGIN
  FOR num IN 1..3 BY 1 LOOP
    LOOP
      EXIT WHEN num >= 3; -- Here
      RAISE INFO  Inner loop:num is %. , num;
      num := num + 1;
    END LOOP;
    RAISE INFO  Outer loop:num is %. , num;
  END LOOP;
END
$$;

产出如下:

INFO:  Inner loop:num is 1.
INFO:  Inner loop:num is 2.
INFO:  Outer loop:num is 3.
INFO:  Inner loop:num is 2.
INFO:  Outer loop:num is 3.
INFO:  Outer loop:num is 3.
DO

友情链接