现有 a 表 和b表
当我删除b表的数据时
a表的 Usercount字段 里面的数据 要减
反之 当我添加的时候
要加1
a表 id imei Usercount 三个字段b表id imei Phone 三个字段而且 phone的数据总数 = Usercount的数据
当我删除b表的数据时
a表的 Usercount字段 里面的数据 要减
反之 当我添加的时候
要加1
a表 id imei Usercount 三个字段b表id imei Phone 三个字段而且 phone的数据总数 = Usercount的数据
for eache row
begin
update a set usercount = usercount-1 where a.imei=old.imei
endcreate trigger t1 after insert on b
for eache row
begin
update a set usercount = usercount+1 where a.imei=old.imei
end
create trigger t1 after delete on b
for eache row
begin
update a set usercount = usercount-1 where a.id=old.id;
end$$
delimiter ;delimiter $$
create trigger t1 after insert on b
for eache row
begin
update a set usercount = usercount+1 where a.id=new.id;
end$$
delimiter ;
for eache row
update a set usercount = usercount-1 where a.imei=old.imei;
create trigger t2 after insert on b
for eache row
update a set usercount = usercount+1 where a.imei=old.imei;
create trigger t1 after delete on b
for each row
begin
update a set usercount=usercount+1 where a.imer=old.imei;
end$$
delimiter;delimiter$$
create trigger t2 after insert on b
for each row
begin
update b set usercount=usercount-1 where a.imei=old.imei;
end$$
delimiter;