MYSQL C API : struct MYSQL_STMT 结构的组合使用

 1 #include <iostream>
 2 #include <string>
 3 
 4 #include <string.h>
 5 #include <assert.h>
 6 
 7 #include <mysql.h>
 8 
 9 static void do_stmt_sql(MYSQL *ms_conn);
10 
11 int main()
12 {
13     // 初始化MYSQL 实例
14     MYSQL *ms_conn = mysql_init(NULL);
15     if (ms_conn == NULL)
16     {
17         std::cout << "mysql init failed." << std::endl;
18         return 0;
19     }
20     std::cout << "mysql init successful." << std::endl;
21 
22     // 连接到MYSQL 服务器
23     MYSQL *ms_ret = mysql_real_connect(ms_conn, "localhost", "suyh", 
24             "suyunhong", "suyh_db", 0, NULL, 0);
25     if (ms_ret == NULL)
26     {
27         std::cout << "mysql connect failed. " 
28             << mysql_error(ms_conn) << std::endl;
29         mysql_close(ms_conn), ms_conn = NULL;
30         return 0;
31     }
32     std::cout << "mysql connect successful." << std::endl;
33 
34     do_stmt_sql(ms_conn);
35 
36     // 释放资源
37     mysql_close(ms_conn), ms_conn = NULL;
38     return 0;
39 }
40 
41 static void do_stmt_sql(MYSQL *ms_conn)
42 {
43     assert(ms_conn != NULL);
44     if (ms_conn == NULL)
45         return ;
46 
47     MYSQL_STMT *stmt = NULL;
48     stmt = mysql_stmt_init(ms_conn);
49     if (stmt == NULL)
50     {
51         std::cout << "stmt is NULL. mysql_stmt_init failed. "
52             << mysql_error(ms_conn) << std::endl;
53         return ;
54     }
55     std::cout << "MYSQL_STMT init successful." << std::endl;
56 
57     const char str_sql[] = "INSERT INTO tb_bin_data(bin_data) VALUES(?)";
58 
59     int res = 0;
60     res = mysql_stmt_prepare(stmt, str_sql, sizeof(str_sql) - 1);
61     if (res != 0)
62     {
63         std::cout << "mysql_stmt_prepare INSERT failed."
64             << mysql_stmt_error(stmt) << std::endl;
65         return ;
66     }
67 
68     // 待存到MYSQL 的二进制数据
69     char bin_data[] = {0, 1, 2, 3, 4, 5, 6, 7, 8, 9};
70 
71     MYSQL_BIND bind[1];
72     memset(bind, 0, sizeof(bind));
73     bind[0].buffer_type = MYSQL_TYPE_BLOB;
74     bind[0].is_null = NULL;
75     bind[0].buffer = bin_data;
76     bind[0].buffer_length = sizeof(bin_data);
77 
78     res = mysql_stmt_bind_param(stmt, bind);
79     if (res != 0)
80     {
81         std::cout << "mysql_stmt_bind_param failed. " 
82             << mysql_stmt_error(stmt) << std::endl;
83         mysql_stmt_close(stmt), stmt = NULL;
84         return ;
85     }
86     std::cout << "mysql_stmt_bind_param successful." << std::endl;
87 
88     // res = mysql_stmt_send_long_data(stmt, 0, escape_bin, strlen(escape_bin));
89     // std::cout << "mysql_stmt_send_long_data result is " << res << std::endl;
90 
91     res = mysql_stmt_execute(stmt);
92     std::cout << "mysql_stmt_execute() func result is " << res << std::endl;
93 
94     mysql_stmt_close(stmt), stmt = NULL;
95 }