Postgresql添加/删除触发器示例

-- 定义触发器
CREATE TRIGGER "vss_after_insert_flow_201702" AFTER INSERT ON "public"."vss_passenger_flow_201702"
FOR EACH ROW
EXECUTE PROCEDURE "vss_after_insert_flow"();

--删除触发器
DROP TRIGGER vss_after_insert_flow_201702 ON vss_passenger_flow_201702 ;

--定义存储过程

-- FUNCTION: public.vss_after_insert_flow()

-- DROP FUNCTION public.vss_after_insert_flow();

CREATE FUNCTION public.vss_after_insert_flow()
    RETURNS trigger
    LANGUAGE ‘plpgsql‘
    COST 100.0
    VOLATILE NOT LEAKPROOF 
AS $BODY$
BEGIN
    --Routine body goes here...
    IF EXISTS(SELECT camera_id FROM vss_passenger_hour 
        WHERE camera_id = NEW.i_camera_id and datetime = NEW.start_dt::DATE and EXTRACT(hour FROM time) = EXTRACT(hour FROM NEW.start_dt::TIME)) THEN
    UPDATE vss_passenger_hour 
        SET passenger_in_count = passenger_in_count + NEW.i_enter_num,passenger_out_count = passenger_out_count + NEW.i_leave_num 
            WHERE camera_id = NEW.i_camera_id and datetime = NEW.start_dt::DATE and EXTRACT(hour FROM time) = EXTRACT(hour FROM NEW.start_dt::TIME);
    ELSE
    INSERT INTO vss_passenger_hour(region_id,camera_id,datetime,time,passenger_in_count,passenger_out_count)
        VALUES (NEW.i_area_id,NEW.i_camera_id,NEW.start_dt,to_timestamp(to_char(NEW.start_dt,‘yyyy-mm-dd HH24‘)||‘:00:00‘,‘yyyy-mm-dd HH24:MI:SS‘),NEW.i_enter_num,NEW.i_leave_num);
    END IF;
    RETURN NULL;
END
$BODY$;

ALTER FUNCTION public.vss_after_insert_flow()
    OWNER TO postgres;