包含头文件
#include <mysql_connection.h>
#include <mysql_driver.h>
#include <cppconn/statement.h>
#include <cppconn/resultset.h>
#include <cppconn/exception.h> #ifdef _DEBUG
#pragma comment(lib, "mysqlcppconn.lib")
#else
#pragma comment(lib, "mysqlcppconn-static.lib")
// 我的MySQL connector/C++是自己下源码编译的,需要引入这个,官方直接提供的二进制我不清楚需要不需要
#pragma comment(lib, "mysqlclient.lib")
#endif
代码
try
{
const char* user = "root";
const char* passwd = "";
const char* host = "tcp://192.168.1.8:3306";
const char* database = "mysql"; sql::mysql::MySQL_Driver* driver = sql::mysql::get_driver_instance();
sql::Connection* conn = driver->connect(host, user, passwd);
conn->setSchema(database); sql::Statement *stmt = conn->createStatement(); sql::ResultSet *res = stmt->executeQuery("select * from user;");
while (res->next()) {
AfxMessageBox((res->getString() + " | " + res->getString()).c_str());
} delete res;
delete stmt;
delete conn; }
catch (sql::SQLException e) {
CString strErrorMsg;
strErrorMsg.Format("MySQL error code %d: %s, %s", e.getErrorCode(), e.what(), e.getSQLState().c_str());
AfxMessageBox(strErrorMsg);
if (e.getErrorCode() == ) {
AfxMessageBox("");
}
}
catch (std::runtime_error e) {
AfxMessageBox(e.what());
}
静态链接
>TestDlg.obj : error LNK2001: 无法解析的外部符号 "__declspec(dllimport) class sql::mysql::MySQL_Driver * __cdecl sql::mysql::get_driver_instance(void)" (__imp_?get_driver_instance@mysql@sql@@YAPAVMySQL_Driver@@XZ)
>TestDlg.obj : error LNK2001: 无法解析的外部符号 "__declspec(dllimport) public: virtual __thiscall sql::SQLException::~SQLException(void)" (__imp_??1SQLException@sql@@UAE@XZ)
>TestDlg.obj : error LNK2001: 无法解析的外部符号 "__declspec(dllimport) public: int __thiscall sql::SQLException::getErrorCode(void)const " (__imp_?getErrorCode@SQLException@sql@@QBEHXZ)
>TestDlg.obj : error LNK2001: 无法解析的外部符号 "__declspec(dllimport) public: class std::basic_string<char,struct std::char_traits<char>,class std::allocator<char> > const & __thiscall sql::SQLException::getSQLState(void)const " (__imp_?getSQLState@SQLException@sql@@QBEABV?$basic_string@DU?$char_traits@D@std@@V?$allocator@D@@@std@@XZ)
>TestDlg.obj : error LNK2001: 无法解析的外部符号 "__declspec(dllimport) public: char const * __thiscall sql::SQLString::c_str(void)const " (__imp_?c_str@SQLString@sql@@QBEPBDXZ)
>TestDlg.obj : error LNK2001: 无法解析的外部符号 "__declspec(dllimport) public: __thiscall sql::SQLString::SQLString(char const * const)" (__imp_??0SQLString@sql@@QAE@QBD@Z)
>TestDlg.obj : error LNK2001: 无法解析的外部符号 "__declspec(dllimport) public: __thiscall sql::SQLString::~SQLString(void)" (__imp_??1SQLString@sql@@QAE@XZ)
通过观察cppconn/build_config.h得知若要得到非__declspec(dllimport)方式的引入需要定义宏CPPCONN_LIB_BUILD
解决方案
在包含头文件前定义宏CPPCONN_LIB_BUILD,告诉链接器MySQL connector是静态库方式编译的即可
#ifndef _DEBUG
#define CPPCONN_LIB_BUILD
#endif #include <mysql_connection.h>
#include <mysql_driver.h>
#include <cppconn/statement.h>
#include <cppconn/resultset.h>
#include <cppconn/exception.h>
#ifdef _DEBUG
#pragma comment(lib, "mysqlcppconn.lib")
#else
#pragma comment(lib, "mysqlcppconn-static.lib")
// 我的MySQL connector/C++是自己下源码编译的,需要引入这个,官方直接提供的二进制我不清楚需要不需要
#pragma comment(lib, "mysqlclient.lib")
#endif