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  • mysql

    #include <iostream>
    #include <vector>
    #include <string>
    #include <mysql.h>
    using namespace std;
    
    int main()
    {
        ios::sync_with_stdio (false);
        MYSQL connection;
        mysql_init (&connection);
        mysql_real_connect (&connection,"localhost", "root", "1234",
                                        "world", 3306, nullptr, 0);
        // mysql_query 是一个值-结果函数
        int query_success = mysql_query (&connection, "SELECT * FROM city LIMIT 10");
        if (query_success == 0){
            // 保存查询结果到 result
            MYSQL_RES* result = mysql_store_result (&connection);
            if (result){
                std::cout << "Number of result: "
                          << static_cast<size_t>(mysql_num_rows(result)) << "
    ";
                // 获取列名
                MYSQL_FIELD* field;
                vector<string> column;
                while ((field = mysql_fetch_field (result))){
                    column.emplace_back(field->name);
                }
                // 或者使用 mysql_num_fields(result); 得到结果的行数
                for (const auto& col : column){
                    cout << col << "	";
                }
                cout << "
    ";
                MYSQL_ROW row;
                while ((row = mysql_fetch_row(result))){
                    for (size_t i = 0; i != column.size(); ++i){
                        std::cout << row[i] << "	";
                    }
                    cout << "
    ";
                }
            }
            mysql_free_result(result);
        }
        mysql_close(&connection);
        return 0;
    }

     再做一些小改动:

    #include <iostream>
    #include <vector>
    #include <string>
    #include <mysql.h>
    using namespace std;
    
    int main()
    {
        ios::sync_with_stdio (false);
        MYSQL connection;
        mysql_init (&connection);
        mysql_real_connect (&connection,"localhost", "root", "1234",
                                        "world", 3306, nullptr, 0);
        // mysql_query 是一个值-结果函数
        int query_success = mysql_query (&connection, "SELECT * FROM city");
        if (query_success == 0){
            // 保存查询结果到 result
            MYSQL_RES* result = mysql_store_result (&connection);
            if (result){
                cout << "Number of result: "
                          << static_cast<size_t>(mysql_num_rows(result)) << "
    ";
                MYSQL_FIELD* field;
                while ((field = mysql_fetch_field (result))){
                    cout << field->name << "	";
                }
                cout << "
    ";
                MYSQL_ROW row;
                auto const field_num = mysql_num_fields(result);
                while ((row = mysql_fetch_row(result))){
                    for (size_t i = 0; i != field_num; ++i){
                        std::cout << row[i] << "	";
                    }
                    cout << "
    ";
                }
            }
            mysql_free_result(result);
        }
        mysql_close(&connection);
        return 0;
    }
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  • 原文地址:https://www.cnblogs.com/wuOverflow/p/5149632.html
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