关闭游标错误MySQL连接器C++ 8

server->get_mysql_session() 返回临时 Session 对象。所有临时文件在其创建声明的结尾处都会被销毁。

因为在你打电话之前会话被破坏了 fetchOne 它失败了。

例如,此代码:

#include <iostream>
#include <string>

struct A
{
    A() { std::cout << "A()\n"; }
    ~A() { std::cout << "~A()\n"; }
};

std::ostream& operator << (std::ostream& os, const A& a) { os << "\nA<<"; return os; }

int main()
{
    std::cout << "line1\n";
    std::cout << "line2" << A() << "\n";
    std::cout << "line3\n";
}

生成以下输出:

line1
A()
line2
A<<
~A()
line3