postgresql 添加触发器

添加触发器

-- 创建触发器函数 CREATE FUNCTION update_kpi_for_path_depth_trigger_fun() returns trigger as $$ begin     DELETE from kpi_path;     WITH RECURSIVE T (kpi_id, NAME, PARENT_ID, PATH, DEPTH,kpi_sql)  AS (     SELECT kpi_id, NAME, PARENT_ID, ARRAY[kpi_id] AS PATH, 1 AS DEPTH,kpi_sql     FROM kpi     WHERE PARENT_ID = 0      UNION ALL     SELECT  D.kpi_id, D.NAME, D.PARENT_ID, T.PATH || D.kpi_id, T.DEPTH + 1 AS DEPTH,D.kpi_sql     FROM kpi D     JOIN T ON D.PARENT_ID = T.kpi_id     )     INSERT INTO kpi_path(kpi_id,name,parent_id,path,depth,kpi_sql)  SELECT kpi_id, NAME, PARENT_ID, PATH, DEPTH,kpi_sql FROM T     ORDER BY PATH;     UPDATE kpi set path =p.path,depth=p.depth from kpi_path p WHERE p.kpi_id=kpi.kpi_id;         RETURN NULL;   -- 返回值是必须的 end; $$ language plpgsql;  -- 基于表和列创建出发器 CREATE TRIGGER update_kpi_for_path_depth_fun_trigger after insert or UPDATE of parent_id on kpi for each row execute procedure update_kpi_for_path_depth_trigger_fun();

来源：博客园

作者：huanglei2010

链接：https://www.cnblogs.com/huanglei2010/p/11474809.html