触发 - postgres

Question

我创建了以下表格

professor
------------------------------------------------------
ProfNr | Name | Room | Bonus
------------------------------------------------------

lecture
--------------------------------------------------
Lecture No | Title | semester hours | held by (Prof Reference)
--------------------------------------------------

我正在寻找postgres下的触发器，使用教授给予奖金的每周课程（薪水）

也许我可以帮助别人，非常棒！

甚至可能触发其他应用的想法

Answer 1

首先，我认为您的奖金应该是另一张表，以便您可以按需汇总。所以这留下了三个表：

CREATE TABLE professor (
   profid serial not null unique,
   ...
);

CREATE TABLE lecture (
   lecture_id serial not null unique,
   professor int not null references professor(profid),
   ...
);

CREATE TABLE prof_bonus (
   lecture_id int references lecture(id),
   profid int references professor (profid),
   bonus_amt numeric not null,
   primary key (lecture_id, profid)
);

CREATE FUNCTION add_bonus() RETURNS TRIGGER LANGUAGE PLPGSQL AS
$$
BEGIN
INSERT INTO prof_bonus (lecture_id, profid, bonus_amt)
VALUES (new.lecture_id, new.profid, 100);
RETURN NEW;
END;
$$;

CREATE TRIGGER add_bonus AFTER INSERT TO lecture FOR EACH ROW 
EXECUTE PROCEDURE add_bonus();