C API 串連MYSQL

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 1 #include <iostream> 2 #include <mysql.h> 3 #include <string> 4  5 #include <assert.h> 6  7  8 int main() 9 {10         // MYSQL 初始化11     MYSQL *ms_conn = mysql_init(NULL);12     if (ms_conn == NULL)13     {14         std::cout << "Error: mysql_init failed." << std::endl;15         return 0;16     }17     std::cout << "Info: mysql_init success." << std::endl;18 19     // 串連到MYSQL 資料庫伺服器，最後參數CLIENT_MULTI_STATEMENTS 指定SQL 可以同時多條。20     MYSQL *ms_temp = NULL;21     ms_temp = mysql_real_connect(ms_conn, "localhost", "root", "123456sx", 22             "suyh", 0, NULL, CLIENT_MULTI_STATEMENTS);23     if (ms_temp == NULL)24     {25         std::cout << "Error: mysql_real_connect() failed." << std::endl;26         mysql_close(ms_conn), ms_conn = NULL;27         return 0;28     }29     std::cout << "Info: mysql_real_connect() succect." << std::endl;30 31     std::string str_sqls = "";32     // str_sqls += "SELECT * FROM player_data WHERE id = 100000;";33     // str_sqls += "SELECT * FROM player_data WHERE id = 100001;";34     str_sqls += "SELECT * FROM player_data WHERE id = 100002";35 36     // 執行SQL 陳述式37     int res = 0;38     res = mysql_real_query(ms_conn, str_sqls.c_str(), str_sqls.size());39     if (res != 0)40     {41         std::cout << "Info: query failed, sql: " << str_sqls.c_str() << std::endl;42         mysql_close(ms_conn), ms_conn = NULL;43         return 0;44     }45     std::cout << "Info: query success." << std::endl;46 47     do48     {49         // 取出查詢結果50         MYSQL_RES *ms_res = mysql_store_result(ms_conn);51         assert(ms_res != NULL);52 53         // 結果集中的欄位個數54         unsigned int field_num = mysql_num_fields(ms_res);55         std::cout << "fileds number is " << field_num << std::endl;56 57         // 每個欄位的結構58         MYSQL_FIELD* field = mysql_fetch_field(ms_res);59         assert(field != NULL);60 61         // 取出這個結果集中的結果62         MYSQL_ROW row_data = NULL;    // typedef char ** MYSQL_ROW;63         while (1)64         {65             row_data = mysql_fetch_row(ms_res);66             if (row_data == NULL)67                 break;    // 結果集中已無資料68 69             // 一行結果中每個欄位的字元數70             unsigned long *field_lens = mysql_fetch_lengths(ms_res);71             assert(field_lens != NULL);72             for (int i = 0; i < field_num; ++i)73             {74                 /*75                 std::cout << "field_lens[" << i << "] = " << field_lens[i]76                     << ", value is " << row_data[i] << std::endl;77                 */78                 std::cout << "field name: " << field[i].name;79                 if (row_data[i] == NULL)80                     std::cout << ", value is NULL" << std::endl;81                 else82                     // std::cout << ", value is " << row_data[i] << std::endl; 83                     std::cout << ", value is NOT NULL" << std::endl;84             }85 86             // ... // 處理結果87         }88     } while (mysql_next_result(ms_conn) == 0);89 90     mysql_close(ms_conn), ms_conn = NULL;91     return 0;92 }

 

C API 串連MYSQL