MYSQL C API : CLIENT_MULTI_STATEMENTS 选项

 #include <iostream>
 #include <mysql.h>
 #include <string>

 #include <assert.h>

 int main()
 {
     MYSQL *ms_conn = mysql_init(NULL);
     if (ms_conn == NULL)
     {
         std::cout << "Error: mysql_init failed." << std::endl;
         return ;
     }
     std::cout << "Info: mysql_init success." << std::endl;

     // 参数CLIENT_MULTI_STATEMENTS 指定一次query 可以执行多条SQL
     MYSQL *ms_temp = NULL;
     ms_temp = mysql_real_connect(ms_conn, "localhost", "root", "123456sx",
             "suyh", , NULL, CLIENT_MULTI_STATEMENTS);
     if (ms_temp == NULL)
     {
         std::cout << "Error: mysql_real_connect() failed." << std::endl;
         std::cout << mysql_error(ms_conn) << std::endl;
         mysql_close(ms_conn), ms_conn = NULL;
         return ;
     }
     std::cout << "Info: mysql_real_connect() succect." << std::endl;

     std::string str_sqls = "";
     str_sqls += "SELECT id, account, sex, level, powers FROM player_data WHERE id = 100000";
     str_sqls += ";";
     str_sqls += "SELECT id, account, sex, level, powers FROM player_data WHERE id = 100001";
     str_sqls += ";";
     str_sqls += "SELECT id, account, sex, level, powers FROM player_data WHERE id = 100002";

     int res = ;
     res = mysql_real_query(ms_conn, str_sqls.c_str(), str_sqls.size());
     if (res != )
     {
         std::cout << "Info: query failed, sql: " << str_sqls.c_str() << std::endl;
         std::cout << mysql_error(ms_conn) << std::endl;
     }
     else
     {
         std::cout << "Info: query success." << std::endl;
         std::cout << std::endl;

         // CLIENT_MULTI_STATEMENTS 指定该选项需要mysql_next_result() 函数来获取下一条结果集
         // 如果结果集未取完，则不能进行query 操作。
         do
         {
             MYSQL_RES *ms_res = mysql_store_result(ms_conn);
             assert(ms_res != NULL);

             unsigned int field_num = mysql_num_fields(ms_res);
             std::cout << "fileds number is " << field_num << std::endl;

             MYSQL_FIELD* field_info = mysql_fetch_field(ms_res);
             assert(field_info != NULL);

             MYSQL_ROW row_data = NULL;
             while ()
             {
                 row_data = mysql_fetch_row(ms_res);
                 if (row_data == NULL)
                     break;

                 unsigned long *field_lens = mysql_fetch_lengths(ms_res);
                 assert(field_lens != NULL);
                 for (int i = ; i < field_num; ++i)
                 {
                     if (field_info[i].type == MYSQL_TYPE_BLOB)
                     {
                         std::cout << "current filed type is BLOB." << std::endl;
                         continue;
                     }

                     if (row_data[i] == NULL)
                     {
                         std::cout << "field_lens[" << i << "] = " << field_lens[i]
                             << ", value is NULL." << std::endl;
                     }
                     else
                     {
                         std::cout << "field_lens[" << i << "] = " << field_lens[i]
                             << ", value is " << row_data[i] << std::endl;
                     }
                 }
             }

             mysql_free_result(ms_res), ms_res = NULL;

             std::cout << "#######################################" << std::endl;
         } while (mysql_next_result(ms_conn) == );
     }

     mysql_close(ms_conn), ms_conn = NULL;
     return ;
 }