数据库 --> MySQL使用

MySQL使用

代码：

#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <unistd.h>  //write头文件
#include <mysql/mysql.h>//包含MySQL头文件
#include <stdio.h>
#include <string.h>
#include <stdlib.h>

void connect_mysql(MYSQL * mysql ,char * str[],MYSQL **connect);
void insert_mysql(MYSQL * mysql);
void delete_mysql(MYSQL * mysql);
void update_mysql(MYSQL * mysql);
void select_mysql(MYSQL * mysql,MYSQL **connect);
void show_table(MYSQL * mysql,MYSQL **connect);
void set_char(MYSQL * mysql);
void menu();
void quit(MYSQL **connect);

int main(int argc,char *argv[])
{
    MYSQL mysql, *connect = NULL;
 
    char *str[] = {argv[1],argv[2],argv[3]};
    connect_mysql(&mysql,str,&connect);
    menu();
    quit(&connect);
    return 0;
}
void set_char(MYSQL *mysql)//设置数据库的字符集  要先做
{
    int i = mysql_query(mysql,"set names utf8");//向mysql服务器端发送指令
    //成功则返回0，失败则返回非0数据
    if(i != 0)
    {
        printf("set char fail!!
");
        return;
    }
 
}
void select_mysql(MYSQL *mysql,MYSQL **connect)
{
    if(!mysql)
        return;
    else{
    write(1,"Input select SQL:
",strlen("Input select SQL:
"));
    char select_sql[256];
    int n=0;
    memset(select_sql,0,sizeof(select_sql));
    for(n;;n++)//读取标准输入直到；在去除；
    {
        select_sql[n]=getchar();
        if(select_sql[n] == ';')
        {
            select_sql[n]=0;
            break;
        }
    }
    char * SQL = select_sql;
    int i = mysql_query(mysql,SQL);
    if(i != 0 )
    {
        printf("Update SQL fail %s 
",mysql_error(mysql));
        return;
    }else
        printf("Update SQL success
");
    }
    MYSQL_RES *res = mysql_store_result(mysql);//返回结果集放入MYSQL_RES中
    int num_fields = mysql_num_fields(res);//查看结果集中行数
 
    MYSQL_ROW row;
    while((row = mysql_fetch_row(res)))//检索一个结果集合的下一行。当在mysql_store_result()之后使用时，
    //没有更多的行可检索时，mysql_etch_row()返回NULL
    {
        int i;
        for(i=0;i<num_fields;i++)
        {
            printf("%s
",row[i]);
 
        }
 
 
 
    }
    mysql_free_result(res);//必须清空结果集########
}
 
void show_table(MYSQL *mysql,MYSQL **connect)
{
    int i = mysql_query(mysql,"show tables");
    if(i != 0)
        return;
    else{
        MYSQL_RES * result = mysql_store_result(*connect);
        int num_fields = mysql_num_fields(result);
        MYSQL_ROW row;
        while((row = mysql_fetch_row(result)))
        {
            int i;
            for(i=0;i<num_fields;i++)
            {
                char *SQL;
                sprintf(SQL,"desc %s",row[i]);
                int n = mysql_query(mysql,SQL);
            MYSQL_RES * res= mysql_store_result(*connect);
//可以调用mysql_fetch_row()来获取结果集中的行，或调用mysql_row_seek()
//和mysql_row_tell()来获取或设置结果集中的当前行位置。
//一旦完成了对结果集的操作，必须调用mysql_free_result()。
            int table_num = mysql_num_fields(res);
            MYSQL_ROW row1;
            while((row1 = mysql_fetch_row(res)))
            {
                int j;
                for(j=0;j<table_num;j++)
                {
                printf("%s
",row1[j]);
 
                }
            }
            mysql_free_result(res);
 
            }
 
        }
        mysql_free_result(result);
    }
 
 
}
 
void update_mysql(MYSQL *mysql)
{
    if(!mysql)
        return;
    else{
    write(1,"Input update SQL:
",strlen("Input update SQL:
"));
    char update_sql[256];
    int n=0;
    memset(update_sql,0,sizeof(update_sql));
    for(n;;n++)
    {
        update_sql[n]=getchar();
        if(update_sql[n] == ';')
        {
            update_sql[n]=0;
            break;
        }
    }
    char * SQL = update_sql;
    int i = mysql_query(mysql,SQL);
    if(i != 0 )
    {
        printf("Update SQL fail %s 
",mysql_error(mysql));
        return;
    }else
        printf("Update SQL success
");
    }
}
 
void delete_mysql(MYSQL *mysql)
{
    if(!mysql)
        return;
    else{
    write(1,"Input delete SQL:
",strlen("Input delete SQL:
"));
    char delete_sql[256];
    int n=0;
    memset(delete_sql,0,sizeof(delete_sql));
    for(n;;n++)
    {
        delete_sql[n]=getchar();
        if(delete_sql[n] == ';')
        {
            delete_sql[n]=0;
            break;
        }
    }
    char * SQL = delete_sql;
    int i = mysql_query(mysql,SQL);
    if(i != 0 )
    {
        printf("Delete SQL fail %s 
",mysql_error(mysql));
        return;
    }else
        printf("Delete SQL success
");
    }
}
 
void insert_mysql(MYSQL *mysql)
{
    if(!mysql)
        return;
    else{
    write(1,"Input insert SQL:
",strlen("Input insert SQL:
"));
    char insert_sql[256];
    int n=0;
    memset(insert_sql,0,sizeof(insert_sql));
    for(n;;n++)
    {
        insert_sql[n]=getchar();
        if(insert_sql[n] == ';')
        {
            insert_sql[n]=0;
            break;
        }
    }
    char * SQL = insert_sql;
    int i = mysql_query(mysql,SQL);
    if(i != 0 )
    {
        printf("Insert SQL fail %s 
",mysql_error(mysql));
        return;
    }else
        printf("Insert SQL success
");
    }
}
void connect_mysql(MYSQL *mysql,char *str[],MYSQL **connect)
{
    char passwd[256];
    memset(passwd,0,sizeof(passwd));
    write(1,"passwd:",strlen("passwd:"));
    scanf("%s",passwd);
    passwd[strlen(passwd)]=0;
    mysql_init(mysql);
    *connect = mysql_real_connect(mysql,str[1],str[2],passwd,str[3],0,0,0);
    if(*connect == NULL)
    {
        printf("Connect database fail! %s
",mysql_error(mysql));
        return;
    }else{
        printf("Connect success!
");
    }
 
}
void quit(MYSQL **connect)
{
    mysql_close(*connect);
    *connect = NULL;
    printf("Bye
");
    exit(1);
}
void menu()
{
    printf("###########################
");
    printf("     A -> SELECT:
");
    printf("     B -> UPDATE:
");
    printf("     C -> DELETE:
");
    printf("     D -> INSERT:
");
    printf("     E -> DESC TABLE:
");
    printf("     Q -> QUIT:
");
    printf("###########################
");
    write(1,"Input: ",strlen("Input: "));
}

1、找不到mysql.h，请安装 

sudo apt-get install libmysqlclient-dev

2、编译不过，加 -lmysqlclient

参考：http://www.oschina.net/code/snippet_2325404_47438