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

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/*
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 test
use test
CREATE 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;
};