带有INSERT as then子句的if语句（MYSQL）

我正在进行有条件的插入，但在进行插入时遇到问题

情况是这样的

if(select count(*) from employee < 3, insert into employee (name) values ("lisa");

您可以这样尝试：

SET some_var = (select count(*) from employee);

if(some_var < 3) then
    insert into employee (name) values ("lisa");
end if

或者

SELECT COUNT(*) AS count into @some_var FROM employee;
if(@some_var < 3) then
    insert into employee (name) values ("lisa");
end if;

您可以这样尝试：

SET some_var = (select count(*) from employee);

if(some_var < 3) then
    insert into employee (name) values ("lisa");
end if

或者

SELECT COUNT(*) AS count into @some_var FROM employee;
if(@some_var < 3) then
    insert into employee (name) values ("lisa");
end if;

试试这个：

insert into employee(name)
    select 'lisa'
   where (select count(*) from employee) < 3;

试试这个：

insert into employee(name)
    select 'lisa'
   where (select count(*) from employee) < 3;