C语言读取文件并插入到mysql数据库

C语言往mysql插入文件直接用“insert into”语句会出现问题，这时候可以改用MYSQL_BIND结构体插入二进制文件。
详细的事例代码如下：（功能包含本地文件的读取和插入）

#include <mysql/mysql.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#define INSERT_SQL "INSERT INTO t_file VALUES (null,?)"
//文件大小
static int size;
//文件流
static char *buf;
static int insert_file(MYSQL*);
int main(int argc, char *argv[]){
    MYSQL *conn;
     
    int sts;
    FILE *pf;
    size_t result; //返回值是读取的内容数量
    pf = fopen("/home/ec2-user/workspace/test/README.md","rb");
    if (pf == NULL) {
        printf(" Open file error\n");
        exit(0);
    }
    // 获取文件大小
    fseek(pf,0,SEEK_END); //指针移到文件末尾
    size = (int)ftell(pf); //获取长度
    rewind(pf); // 函数rewind()把文件指针移到由stream(流)指定的开始处, 同时清除和流相关的错误和EOF标记  
    buf = (char*)malloc(sizeof(char)*size);
    result = fread(buf,1,size,pf);
    if (result != size) {
        printf(" Read file error\n");
        exit(0);
    }
    printf("size:%d\n",size);
    //mysql初始化
    conn = mysql_init(NULL);
    if (conn == NULL) {
        printf("Error %u: %s\n", mysql_errno(conn), mysql_error(conn));
        exit(0);
    }
    //连接Mysql
    //if (mysql_real_connect(conn, "localhost", "user", "pass", "database", 0, NULL, 0) == NULL) { 
    if (mysql_real_connect(conn, "127.0.0.1", "root", "123456", "test", 0, NULL, 0) == NULL) {
        printf("Error %u: %s\n", mysql_errno(conn), mysql_error(conn));
        exit(0);
    }
    sts = insert_file(conn);
    if (sts) {
        printf(" Insert file error\n");
        exit(0);
    }
    //释放资源    
    mysql_close(conn); 
     
    fclose(pf);
    free(buf);
    return 0;
}
/*
 * 插入文件
 */
int insert_file(MYSQL *conn) {
     
    MYSQL_STMT *stmt;
    MYSQL_BIND bind[1];
     
    //SQL状态初始化
    stmt = mysql_stmt_init(conn);
    if (!stmt) {
        fprintf(stderr, " mysql_stmt_init(), out of memory\n"); 
        exit(0);
    }
    //预处理
    if (mysql_stmt_prepare(stmt, INSERT_SQL, strlen(INSERT_SQL))) {
        fprintf(stderr, " mysql_stmt_prepare(), INSERT failed: %s\n", mysql_stmt_error(stmt));
        return -1;
    }
    //MEDIUMBLOB PARAM
    bind[0].buffer_type = MYSQL_TYPE_LONG_BLOB;
    //bind[0].buffer_type = MYSQL_TYPE_MEDIUM_BLOB;
    bind[0].buffer = buf;
    bind[0].buffer_length = size;
    bind[0].is_null = 0;
    bind[0].length = 0;
    //解析
    if (mysql_stmt_bind_param(stmt, bind)){
        fprintf(stderr, " mysql_stmt_bind_param() failed: %s\n", mysql_stmt_error(stmt));
        return -1;
    }
    //执行
    if (mysql_stmt_execute(stmt)) {
        fprintf(stderr, " mysql_stmt_execute(), 1 failed: %s\n", mysql_stmt_error(stmt));
        return -1;
    }
    //关闭
    if (mysql_stmt_close(stmt)) {
        fprintf(stderr, " mysql_stmt_close(), 1 failed: %s\n", mysql_stmt_error(stmt));
        return -1;
    }
    return 0;
}

该项目的代码已放到github上，地址： https://github.com/iManville/test

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