Oracle触发器查询统计本表
Oracle触发器查询统计本表,这次由于项目需要,实际动手演练了一把,达到了需要的效果,大致是插入数据后,统计表内和当前插入数
Oracle触发器查询统计本表
这次由于项目需要,实际动手演练了一把,达到了需要的效果,大致是插入数据后,,统计表内和当前插入数据时间相同的个数。
采用行级触发器+语句级触发器。
--包
CREATE OR REPLACE PACKAGE UPDATECASE AS
TYPE T_DATE IS TABLE OF date INDEX BY BINARY_INTEGER;
V_UPDATETIME T_DATE;
V_ROW BINARY_INTEGER := 0;
end;
--行级触发器
create or replace trigger Tri_student_row
after insert or update or delete
on student
FOR EACH ROW
BEGIN
updatecase.V_ROW := updatecase.V_ROW + 1;
if DELETING then
updatecase.V_UPDATETIME(updatecase.V_ROW) := :OLD.CREATETIME;
else
updatecase.V_UPDATETIME(updatecase.V_ROW) := :NEW.CREATETIME;
end if;
END;
--语句级触发器
create or replace trigger Tri_student
after insert or update or delete on student
declare
studentcount number(38,5);
BEGIN
FOR V_LOOP IN 1 .. UPDATECASE.V_ROW LOOP
select count(*)
into studentcount from student t
where t.createtime = UPDATECASE.V_UPDATETIME(V_LOOP);
insert into personcount(comedate,count)values(UPDATECASE.V_UPDATETIME(V_LOOP),studentcount);
end loop;
UPDATECASE.V_ROW := 0;
END;

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