小编use*_*853的帖子

如何包含需要监控的列？即WHEN我想要三个WHEN条件而不是一个条件：

CREATE  TRIGGER freeradius.insert_into_day_summations 
     BEFORE INSERT ON freeradius.day_guiding_usage
     FOR EACH ROW 
     WHEN (OLD.col1 IS DISTINCT FROM NEW.col1)
     WHEN (OLD.col2 IS DISTINCT FROM NEW.col2)
     WHEN (OLD.col3 IS DISTINCT FROM NEW.col3)
EXECUTE procedure update_sessioninfo();