ODBC api 的简单应用

ODBC api 的简单应用

转自：http://www.cnblogs.com/NoSoul/archive/2012/09/16/2687336.html

SQL:

create database ckkc;
create table users
(
name char(35) not null primary key,
psw char(50) not null
)

create table op
(
id int not null primary key auto_increment,
flag int not null,
pname char(15) not null,
num int not null
)

create table st
(
pname char(15) not null primary key,
num int not null
)

insert into users values('root','rootpass');

main.c

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <windows.h>
#include <sql.h>
#include <sqlext.h>
#include <Sqltypes.h>

#define MAXBUFLEN 255
#define Clr() system("cls")
#define Pau() system("pause")

char Str_1[MAXBUFLEN];
char Name[MAXBUFLEN];
SQLHENV henv;
SQLHDBC hdbc;
SQLHSTMT hstmt;
SQLRETURN ret;
SQLCHAR ConnectIn[MAXBUFLEN]="DRIVER={MySQL ODBC 5.1 Driver};SERVER=127.0.0.1;UID=root;PWD=rootpass;DATABASE=ckkc;CharSet=gbk;";
SQLCHAR ConnectOut[MAXBUFLEN];
SQLCHAR sql[MAXBUFLEN];
SQLCHAR    Rs[MAXBUFLEN];
SQLINTEGER cbRS=SQL_NTS;

void Menu()
{
    printf("\n\n\n");
    printf("\t----------------------------------------\n");
    printf("\t\t欢迎登入仓库库存管理系统\n");
    printf("\t----------------------------------------\n");
    printf("请输入用户名:");
    scanf("%s",Name);
    printf("请输入密码:");
    scanf("%s",Str_1);
    return;
}

void Add()
{
    int num;
    printf("请输入入库物品名称:");
    scanf("%s",Str_1);
    printf("请输入入库数量:");
    scanf("%d",&num);
    ret=SQLAllocHandle(SQL_HANDLE_STMT,hdbc,&hstmt);
    wsprintf((LPSTR)sql,"INSERT INTO op(flag,pname,num) VALUES('0','%s','%d')",Str_1,num);
    ret=SQLPrepare(hstmt,sql,SQL_NTS);
    ret=SQLExecute(hstmt);
    if(!SQL_SUCCEEDED(ret))
    {
        printf("2.操作数据库失败!\n");
        return ;
    }
    Rs[0]='\0';
    ret=SQLAllocHandle(SQL_HANDLE_STMT,hdbc,&hstmt);
    wsprintf((LPSTR)sql,"SELECT * FROM st WHERE pname='%s'",Str_1);
    ret=SQLPrepare(hstmt,sql,SQL_NTS);
    ret=SQLExecute(hstmt);
    if(SQLFetch(hstmt)!=SQL_NO_DATA_FOUND)
    {
        SQLGetData(hstmt,1,SQL_C_CHAR,Rs,MAXBUFLEN,&cbRS);
    }
    if(Rs[0]=='\0')
    {
        ret=SQLAllocHandle(SQL_HANDLE_STMT,hdbc,&hstmt);
        wsprintf((LPSTR)sql,"INSERT INTO st VALUES('%s','%d')",Str_1,num);
        ret=SQLPrepare(hstmt,sql,SQL_NTS);
        ret=SQLExecute(hstmt);
        if(!SQL_SUCCEEDED(ret))
        {
            printf("3.操作数据库失败!\n");
            return ;
        }
    }
    else
    {
        ret=SQLAllocHandle(SQL_HANDLE_STMT,hdbc,&hstmt);
        wsprintf((LPSTR)sql,"UPDATE st SET num=num+%d WHERE pname='%s'",num,Str_1);
        ret=SQLPrepare(hstmt,sql,SQL_NTS);
        ret=SQLExecute(hstmt);
        if(!SQL_SUCCEEDED(ret))
        {
            printf("4.操作数据库失败!\n");
            return ;
        }
    }
    return;
}

void Mus()
{
    int num,now;
    printf("请输入出库物品名称:");
    scanf("%s",Str_1);
    printf("请输入出库数量:");
    scanf("%d",&num);
    Rs[0]='\0';
    ret=SQLAllocHandle(SQL_HANDLE_STMT,hdbc,&hstmt);
    wsprintf((LPSTR)sql,"SELECT * FROM st WHERE pname='%s'",Str_1);
    ret=SQLPrepare(hstmt,sql,SQL_NTS);
    ret=SQLExecute(hstmt);
    if(SQLFetch(hstmt)!=SQL_NO_DATA_FOUND)
    {
        SQLGetData(hstmt,2,SQL_C_CHAR,Rs,MAXBUFLEN,&cbRS);
    }
    if(Rs[0]=='\0')
    {
        printf("该货物不存在!\n");
        return;
    }
    else
    {
        now=atoi((const char *)Rs);
        if(now>num)
        {
            ret=SQLAllocHandle(SQL_HANDLE_STMT,hdbc,&hstmt);
            wsprintf((LPSTR)sql,"UPDATE st SET num=num-%d WHERE pname='%s'",num,Str_1);
            ret=SQLPrepare(hstmt,sql,SQL_NTS);
            ret=SQLExecute(hstmt);
            if(!SQL_SUCCEEDED(ret))
            {
                printf("5.操作数据库失败!\n");
                return ;
            }
            ret=SQLAllocHandle(SQL_HANDLE_STMT,hdbc,&hstmt);
            wsprintf((LPSTR)sql,"INSERT INTO op(flag,pname,num) VALUES('1','%s','%d')",Str_1,num);
            ret=SQLPrepare(hstmt,sql,SQL_NTS);
            ret=SQLExecute(hstmt);
            if(!SQL_SUCCEEDED(ret))
            {
                printf("6.操作数据库失败!\n");
                return ;
            }
        }
        else if(now==num)
        {
            ret=SQLAllocHandle(SQL_HANDLE_STMT,hdbc,&hstmt);
            wsprintf((LPSTR)sql,"DELETE FROM st WHERE pname='%s'",Str_1);
            ret=SQLPrepare(hstmt,sql,SQL_NTS);
            ret=SQLExecute(hstmt);
            if(!SQL_SUCCEEDED(ret))
            {
                printf("7.操作数据库失败!\n");
                return ;
            }
            ret=SQLAllocHandle(SQL_HANDLE_STMT,hdbc,&hstmt);
            wsprintf((LPSTR)sql,"INSERT INTO op(flag,pname,num) VALUES('1','%s','%d')",Str_1,num);
            ret=SQLPrepare(hstmt,sql,SQL_NTS);
            ret=SQLExecute(hstmt);
            if(!SQL_SUCCEEDED(ret))
            {
                printf("8.操作数据库失败!\n");
                return ;
            }
        }
        else
        {
            printf("库存不足!\n");
        }
    }
    return;
}

void Query()
{
    SQLINTEGER num;
    SQLINTEGER cbnum;
    printf("货物名称\t数量\n");
    ret=SQLAllocHandle(SQL_HANDLE_STMT,hdbc,&hstmt);
    wsprintf((LPSTR)sql,"SELECT * FROM st",SQL_NTS);
    ret=SQLPrepare(hstmt,sql,SQL_NTS);
    ret=SQLExecute(hstmt);
    if(SQLFetch(hstmt)==SQL_NO_DATA_FOUND)
    {
        printf("记录为空!\n");
    }
    else
    {
        do
        {
            SQLGetData(hstmt,1,SQL_C_CHAR,Rs,MAXBUFLEN,&cbRS);
            SQLGetData(hstmt,2,SQL_C_LONG,&num,0,&cbnum);
            printf("%s\t%ld\n",Rs,num);
        }
        while(SQLFetch(hstmt)!=SQL_NO_DATA_FOUND);
    }
    return;
}

void Show()
{
    SQLINTEGER num,flag;
    SQLINTEGER cbnum,cbflag;
    printf("入/出库\t货物名称\t数量\n");
    ret=SQLAllocHandle(SQL_HANDLE_STMT,hdbc,&hstmt);
    wsprintf((LPSTR)sql,"SELECT * FROM op",SQL_NTS);
    ret=SQLPrepare(hstmt,sql,SQL_NTS);
    ret=SQLExecute(hstmt);
    if(SQLFetch(hstmt)==SQL_NO_DATA_FOUND)
    {
        printf("记录为空!\n");
    }
    else
    {
        do
        {
            SQLGetData(hstmt,2,SQL_C_LONG,&flag,0,&cbflag);
            SQLGetData(hstmt,3,SQL_C_CHAR,Rs,MAXBUFLEN,&cbRS);
            SQLGetData(hstmt,4,SQL_C_LONG,&num,0,&cbnum);
            if(flag==0)
            {
                printf("入");
            }
            else
            {
                printf("出");
            }
            printf("\t%s\t%ld\n",Rs,num);
        }
        while(SQLFetch(hstmt)!=SQL_NO_DATA_FOUND);
    }
    return;
}

int main()
{
    ret=SQLAllocHandle(SQL_HANDLE_ENV,SQL_NULL_HANDLE,&henv);
    ret=SQLSetEnvAttr(henv,SQL_ATTR_ODBC_VERSION,(void *)SQL_OV_ODBC3,0);

    ret=SQLAllocHandle(SQL_HANDLE_DBC,henv,&hdbc);
    ret=SQLDriverConnect(hdbc,NULL,ConnectIn,SQL_NTS,ConnectOut,MAXBUFLEN,(SQLSMALLINT *)0,SQL_DRIVER_NOPROMPT);
    if(!SQL_SUCCEEDED(ret))
    {
        printf("1.操作数据库失败!\n");
        return -1;
    }
    while(1)
    {
        Menu();
        ret=SQLAllocHandle(SQL_HANDLE_STMT,hdbc,&hstmt);
        wsprintf((LPSTR)sql,"SELECT psw FROM users WHERE name ='%s'",Name);
        ret=SQLPrepare(hstmt,sql,SQL_NTS);
        ret=SQLExecute(hstmt);
        if(SQLFetch(hstmt)!=SQL_NO_DATA_FOUND)
        {
            SQLGetData(hstmt,1,SQL_C_CHAR,Rs,MAXBUFLEN,&cbRS);
        }
        if(strcmp((const char *)Rs,Str_1)==0)
        {
            Clr();
            while(1)
            {
                printf("HI %s,欢迎您!\n",Name);
                printf("\t1.入库操作\n");
                printf("\t2.出库操作\n");
                printf("\t3.库存查询\n");
                printf("\t4.交易查询\n");
                printf("\t0.退出系统\n");
                printf("请选择操作:");
                char ch;
                scanf("%*c%c",&ch);
                switch(ch)
                {
                case '1':
                    Add();
                    break;
                case '2':
                    Mus();
                    break;
                case '3':
                    Query();
                    break;
                case '4':
                    Show();
                    break;
                case '0':
                    return 0;
                default:
                    printf("输入错误,请输入0～4\n");
                }
                Pau();
                Clr();
            }
        }
        else
        {
            printf("登录失败!\n");
            Pau();
            Clr();
        }
    }
    return 0;
}