用mysql存储二进制数据流

近日一项目遇到需要在DB中存储2进制数据流类型文件的问题，发现常用的mysql API都用不了，再研究，方知有一套专门的API来干这种数据，功能相当强大的说。

以下即为范例代码 --- 按照说明编译即可用，稍加修改即可存储2进制文件

view plaincopy to clipboardprint?/*mysql数据库存储二进制数据 linux; 用途: 用 mysql_stmt_send_long_data()来向blob字段写入2进制数据流.; 注意点：需要注意的是bind结构的buffer_type字段，必须与要输入的数据类型相符，; 如：只写入一个long 数据，则用MYSQL_TYPE_LONG，写入字符流，用MYSQL_TYPE_STRING,; 写入2进制数据流，用MYSQL_TYPE_BLOB; 具体这个参数各字段的含义参见 mysql5.0手册; Compile: g++ -I/usr/include/mysql -L/usr/lib/mysql -lmysqlclient mysql_test.cpp; 准备工作:; create database testuse testCREATE TABLE `bintest` (; `id` int(11) NOT NULL default '0',; `data` blob; ) ENGINE=MyISAM*/; #include <mysql.h>#include <string.h>#include <stdio.h>#include <stdlib.h> #define INSERT_QUERY 'INSERT INTO bintest(id, data) VALUES(4, ?)' void test(){MYSQL_BIND bind[1];unsigned long;;;;length; char blog_data[100] = {0};memset(blog_data, 0x01, sizeof(blog_data)); char* pos = blog_data;int size = 50; MYSQL *mysql = mysql_init(NULL);if (!mysql) return;;if (!mysql_real_connect(mysql, '192.168.xx.xxx', 'root', 'db_user_name', 'test', 3306, NULL, 0));{ int ret = mysql_errno(mysql);; mysql_close(mysql); return;} MYSQL_STMT *stmt = mysql_stmt_init(mysql);if (!stmt){ fprintf(stderr, ' mysql_stmt_init(), out of memoryn'); exit(0);}if (mysql_stmt_prepare(stmt, INSERT_QUERY, strlen(INSERT_QUERY))){ fprintf(stderr, 'n mysql_stmt_prepare(), INSERT failed'); fprintf(stderr, 'n %s', mysql_stmt_error(stmt)); exit(0);}memset(bind, 0, sizeof(bind));//bind[0].buffer_type= MYSQL_TYPE_STRING;//bind[0].buffer_type = MYSQL_TYPE_LONG;bind[0].buffer = blog_data;//bind[0].buffer_type = MYSQL_TYPE_TINY;bind[0].buffer_type = MYSQL_TYPE_BLOB;bind[0].length= &length;bind[0].is_null= 0; /* Bind the buffers */; if (mysql_stmt_bind_param(stmt, bind)){ fprintf(stderr, 'n param bind failed'); fprintf(stderr, 'n %s', mysql_stmt_error(stmt)); exit(0);} int rc =0;/* Supply data in chunks to server */; if (mysql_stmt_send_long_data(stmt,0, pos, size)){ fprintf(stderr, 'n send_long_data failed'); fprintf(stderr, 'n %s', mysql_stmt_error(stmt)); exit(0);} pos += size; /* Supply the next piece of data */; if (mysql_stmt_send_long_data(stmt,0, pos, size)){ fprintf(stderr, 'n send_long_data failed'); fprintf(stderr, 'n %s', mysql_stmt_error(stmt)); exit(0);} /* Now, execute the query */; if (mysql_stmt_execute(stmt)){ fprintf(stderr, 'n mysql_stmt_execute failed'); fprintf(stderr, 'n %s', mysql_stmt_error(stmt)); exit(0);};} int main(){test();//sleep(1);return 0;};