C语言连接MySQL（codeblocks）

浏览数：20 / 时间：2015年06月12日

#include <stdio.h>
#include <winsock2.h>
#include <mysql.h>
/*数据库连接用宏*/
#define HOST "localhost"
#define USERNAME "root"
#define PASSWORD "root"
#define DATABASE "mysql"

int main()
{
    char *query;
    query="select host,user from user";
    query_sql(query);
    return 0;
}
void query_sql(char* sql)
{
    MYSQL my_connection; /*这是一个数据库连接*/
    int res; /*执行sql語句后的返回标志*/
    MYSQL_RES *res_ptr; /*指向查询结果的指针*/
    MYSQL_FIELD *field; /*字段结构指针*/
    MYSQL_ROW result_row; /*按行返回的查询信息*/
    int row, column; /*查询返回的行数和列数*/
    int i, j;
    /*初始化mysql连接my_connection*/
    mysql_init(&my_connection);
    /*建立mysql连接*/
    if (NULL != mysql_real_connect(&my_connection, HOST, USERNAME, PASSWORD,
                                   DATABASE, 0, NULL, CLIENT_FOUND_ROWS))  /*连接成功*/
    {
        printf("数据库查询query_sql连接成功！\n");
        /*设置查询编码为gbk，以支持中文*/
        mysql_query(&my_connection, "set names gbk");
        res = mysql_query(&my_connection, sql);
        if (res)   /*执行失败*/
        {
            printf("Error： mysql_query !\n");
            /*关闭连接*/
            mysql_close(&my_connection);
        }
        else     /*现在就代表执行成功了*/
        {
            /*将查询的結果给res_ptr*/
            res_ptr = mysql_store_result(&my_connection);
            /*如果结果不为空，就把结果print*/
            if (res_ptr)
            {
                /*取得結果的行数和*/
                column = mysql_num_fields(res_ptr);
                row = mysql_num_rows(res_ptr);
                printf("查询到 %d 行 \n", row);
                /*输出結果的字段名*/
                for (i = 0; field = mysql_fetch_field(res_ptr); i++)
                    printf("%10s ", field->name);
                printf("\n");
                /*按行输出結果*/
                for (i = 1; i < row+1; i++)
                {
                    result_row = mysql_fetch_row(res_ptr);
                    for (j = 0; j < column; j++)
                        printf("%10s ", result_row[j]);
                    printf("\n");
                }
            }
            /*不要忘了关闭连接*/
            mysql_close(&my_connection);
        }
    }
    else
    {
        printf("数据库连接失败");
    }
}

<p style="line-height: 21px; margin: 10px auto; font-family: Verdana, Geneva, Arial, Helvetica, sans-serif; font-size: 14px;"> 注意事项：</p><p style="line-height: 21px; margin: 10px auto; font-family: Verdana, Geneva, Arial, Helvetica, sans-serif; font-size: 14px;">1.在Linker settings->Link libraries中添加libmysql.lib的路径</p><p style="line-height: 21px; margin: 10px auto; font-family: Verdana, Geneva, Arial, Helvetica, sans-serif; font-size: 14px;">2.在Search directories->的Compiler中添加mysql.h的文件夹路径</p><p style="line-height: 21px; margin: 10px auto; font-family: Verdana, Geneva, Arial, Helvetica, sans-serif; font-size: 14px;">（总之就是让编译器能找到libmysql.lib和mysql.h）</p><p style="line-height: 21px; margin: 10px auto; font-family: Verdana, Geneva, Arial, Helvetica, sans-serif; font-size: 14px;">3.在#include <mysql.h>之前添加#include <winsock2.h>（网上很多资料没有这一步，但是我这边实际操作时发现不加这一句编译无法通过）</p><p style="line-height: 21px; margin: 10px auto; font-family: Verdana, Geneva, Arial, Helvetica, sans-serif; font-size: 14px;"><img src="http://img.blog.csdn.net/20150606165538070?watermark/2/text/aHR0cDovL2Jsb2cuY3Nkbi5uZXQvcXFfMjA0ODA2MTE=/font/5a6L5L2T/fontsize/400/fill/I0JBQkFCMA==/dissolve/70/gravity/Center" alt="" />
</p><p style="line-height: 21px; margin: 10px auto; font-family: Verdana, Geneva, Arial, Helvetica, sans-serif; font-size: 14px;"><img src="http://img.blog.csdn.net/20150606165654978?watermark/2/text/aHR0cDovL2Jsb2cuY3Nkbi5uZXQvcXFfMjA0ODA2MTE=/font/5a6L5L2T/fontsize/400/fill/I0JBQkFCMA==/dissolve/70/gravity/Center" alt="" />
</p><p style="line-height: 21px; margin: 10px auto; font-family: Verdana, Geneva, Arial, Helvetica, sans-serif; font-size: 14px;">运行结果：</p><p style="line-height: 21px; margin: 10px auto; font-family: Verdana, Geneva, Arial, Helvetica, sans-serif; font-size: 14px;"><img src="http://img.blog.csdn.net/20150606170050484?watermark/2/text/aHR0cDovL2Jsb2cuY3Nkbi5uZXQvcXFfMjA0ODA2MTE=/font/5a6L5L2T/fontsize/400/fill/I0JBQkFCMA==/dissolve/70/gravity/Center" alt="" />
</p>