create tigger test on tb for update as begin if update(实际人数) update tb set 实际人数=实际人数+1 end
--try create tigger test on tb for update as begin if (select count(1) from tb)<(select count(1) from inserted) update tb set 实际人数=实际人数+1 else update tb set 实际人数=实际人数-1 end
for update
as
begin
if update(实际人数)
update tb set 实际人数=实际人数+1
end
create tigger test on tb
for update
as
begin
if (select count(1) from tb)<(select count(1) from inserted)
update tb set 实际人数=实际人数+1
else
update tb set 实际人数=实际人数-1
end