PostgreSQL-function、trigger

增加一个自动记录更新时间的触发器，

第一步，先写一个函数，返回触发器类型的

create function spam_keyword_update_trigger()
returns trigger as 
$$
begin
NEW.tm_update := current_timestamp(0);
return new;
end;
$$
language plpgsql;

第二步，添加调用函数的触发器，在这里我把触发器名称和函数名称设为一样的

create trigger spam_keyword_update_trigger before update on spam_keyword 
for each row execute procedure spam_keyword_update_trigger();

 

了解一张表有哪些触发器

\d table_name

了解触发器所引用函数的定义

\sf function_name

了解一共有哪些自己可见的函数

\df

 

 

行类型
create or replace function thaha(ooo website)returns text as $$
declare
t2_row record;
BEGIN
select into t2_row gid from board where fid=52163;
-- RAISE EXCEPTION 'employee % not found', ooo.name;
return ooo||ooo.url||t2_row.gid;
END;
$$language plpgsql;

select thaha(website) from website  where fid=52163



create or replace function funcx1() returns setof text as $$
declare
i spam_keyword.word%type;
o text ;
begin
for i in select kid from spam_keyword loop
o:=i;
return next o;
end loop;
end;
$$language plpgsql;

select funcx1()
drop function funcx1()