C语言写数据库（二）

简单的实现增删查改的操作后，实现了一个先读写其中一个表的某两项内容，再把相关字符段写入到另外一张表中去。涉及到查询和插入两个步骤。

其中还涉及到汉字的读写和插入，会有字符的操作产生乱码。所以要先保证mysql的汉字字符编码，linux终端字符编码都是统一的。

/*** 
QueryAndInsert
***/
#include<stdio.h>
#include<string.h>
#include<stdlib.h>
#include"mysql.h"

int main()
{
    printf("version = 1.0\n");
    MYSQL mysql;
    MYSQL_RES * res;
    MYSQL_ROW row;
    int r;
    char* query;
    char taskID[256],taskName[256];
    char insert[256];
    int flag;

    mysql_init(&mysql);
    //mysql_options(&mysql, MYSQL_SET_CHARSET_NAME, "gdk");
    if(!mysql_real_connect(&mysql,"localhost","root","mysql123","csql",0,NULL,0))
    {
        printf("Can't connect  the mysql ! errInfo = [ %s ] ",mysql_error(&mysql));
    }
    else
    {
        //query part
        printf("connect the mysql successfully! \n");
        query = "select taskID,taskName from task where taskState=4 order by taskLastEditTime desc";
        mysql_query(&mysql, "set names utf8");
        flag = mysql_real_query(&mysql,query,(unsigned int )strlen(query));
        if(flag)
        {
            printf("query failed\n");
            return 0;
        }
        else
        {
            printf("[%s] made....\n",query);
            res = mysql_store_result(&mysql);
            while(row = mysql_fetch_row(res))
            {    
                sprintf(taskID,"%s",row[0]);
                sprintf(taskName,"%s",row[1]);
            }
        }
    }
    printf("taskID =  %s, taskName = %s\n",taskID,taskName);
    sprintf(insert,"insert into EnvironmentRealData (TaskID,taskName) values(\'%s\',\'%s\');",taskID,taskName);
    printf("insert = %s\n",insert);

//insert

    if(mysql_real_query(&mysql,insert,(unsigned int)strlen(insert)))
    {
        printf("insert data  is faile\n");
        return 0;
    }
    else
    {
        printf("Insert successfully\n");
    }

    mysql_close(&mysql);
    return 0;
}

gcc编译：gcc QueryAndInsert.c -o QueryAndInsert -I /usr/inlcude/mysql -L /usr/lib/mysql -lmysqlclient