分支语句
单分支语句
如果条件成立则执行
if 条件 then
SQL
end if;
-- 如果条件为1,则向classes添加一条记录
create procedure test04(in a int)
begin
if a = 1 then
insert into classes(class_id,class_name,class_remark)
values(5,'vue01','eee');
end if;
end;
call test04(2);
双分支语句
if条件执行
如果条件成立则执行SQL1,否则执行SQL2
if 条件 then
SQL1
else
SQL2
end if;
-- 如果条件为1,则向classes添加一条记录,如果条件是2,则向students中添加数据
create procedure test04(in a int)
begin
if a = 1 then
insert into classes(class_id,class_name,class_remark)
values(5,'vue01','eee');
else
insert into students(stu_num,stu_name,stu_gender,stu_age,cid)
values(10,'王鑫龙','男',21,4);
end if;
end;
call test04(2);
case条件执行
case
when 条件1 then
sql1
when 条件2 then
sql2
......
else
sql n(如果条件都不满足,则执行此SQL)
end case;
-- 如果条件为1,则向classes添加一条记录,如果条件是2,则向students中添加数据
create procedure test02(in a int)
begin
case
when a = 1 then
insert into classes(class_name,class_remark)
values('vue02','fff');
when a = 2 then
insert into students(stu_num,stu_name,stu_gender,stu_age,cid)
values(12140211,'张国芳','男',21,4);
else
update students set stu_name = '李亮' where stu_num = 12140211;
end case;
end;
call test02(1);