8.20网络编程——sqlite3数据库

一、思维导图

二、学生管理系统

1、myhead.h

#ifndef __MYHEAD_H__
#define __MYHEAD_H__#include <string.h>
#include <stdio.h>
#include <stdlib.h>
#include <errno.h>#define ERR_MSG(msg) do{perror(msg);printf("%d\n",__LINE__);return -1;}while(0)
#include <unistd.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <time.h>
#include <pwd.h>
#include <grp.h>
#include <sys/wait.h>
#include <pthread.h>
#include <semaphore.h>
#include <signal.h>
#include <sys/ipc.h>
#include <sys/shm.h>
#include <arpa/inet.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <netinet/ip.h>
#include <sys/msg.h>
#include <sqlite3.h>
#endif

2、代码

#include <myhead.h>
int do_add(sqlite3 *ppDb)
{int add_numb;char add_name[20];char add_sex[10];double add_scare;printf("输入学号:");scanf("%d",&add_numb);printf("输入姓名:");scanf("%s",add_name);printf("输入性别:");scanf("%s",add_sex);printf("输入成绩:");scanf("%lf",&add_scare);char sql[128]={};sprintf(sql,"insert into STUINFO values(%d,\"%s\",\"%s\",%lf);",add_numb,add_name,add_sex,add_scare);char *errmsg=NULL;if(sqlite3_exec(ppDb,sql,NULL,NULL,&errmsg)!=SQLITE_OK){printf("%d\t%s\n",__LINE__,errmsg);sqlite3_free(errmsg);return -1;}printf("添加学生信息成功\n");return 0;
}
int do_delete(sqlite3 *ppDb)
{int delate_numb;printf("输入要删除的学号:");scanf("%d",&delate_numb);char sql[128]={};sprintf(sql,"delete from STUINFO where numb==%d",delate_numb);char *errmsg=NULL;if(sqlite3_exec(ppDb,sql,NULL,NULL,&errmsg)!=SQLITE_OK){printf("%d\t%s\n",__LINE__,errmsg);sqlite3_free(errmsg);return -1;}printf("删除学生信息成功\n");return 0;}
int do_update(sqlite3 *ppDb)//修改学生信息
{int update_numb;char update_name[20];char update_sex[10];double update_scare;printf("输入要修改学号:");scanf("%d",&update_numb);printf("输入修改后的姓名:");scanf("%s",update_name);printf("输入修改后的性别:");scanf("%s",update_sex);printf("输入修改后的成绩:");scanf("%lf",&update_scare);char sql[128]={};sprintf(sql,"update STUINFO set name=\"%s\",sex=\"%s\",scare=%lf where numb=%d;",update_name,update_sex,update_scare,update_numb);char *errmsg=NULL;if(sqlite3_exec(ppDb,sql,NULL,NULL,&errmsg)!=SQLITE_OK){printf("%d\t%s\n",__LINE__,errmsg);sqlite3_free(errmsg);return -1;}printf("修改学生信息成功\n");return 0;
}
int call_back(void *arg,int clos,char **msgtxt,char **msgheader)
{if(*((int *)arg)==0){*((int *)arg)=1;for(int i=0;i<clos;i++){printf("%s\t",*(msgheader+i));}printf("\n");}for(int i=0;i<clos;i++){printf("%s\t",*(msgtxt+i));}printf("\n");return 0;
}
int do_search(sqlite3 *ppDb)
{char sql[128]="select * from STUINFO;";char *errmsg=NULL;int flag=0;if(sqlite3_exec(ppDb,sql,call_back,&flag,&errmsg)!=SQLITE_OK){printf("%d\t%s\n",__LINE__,errmsg);sqlite3_free(errmsg);return -1;}return 0;}
int main(int argc, const char *argv[])
{//创建库sqlite3 *ppDb=NULL;if(sqlite3_open("./db.db",&ppDb)!=SQLITE_OK){printf("sqlist3_open error\n");return -1;}//创建表格char *sql="create table if not exists STUINFO(numb int,name char,sex char,scare double);";char *errmsg=NULL;if(sqlite3_exec(ppDb,sql,NULL,NULL,&errmsg)!=SQLITE_OK){printf("%d\t%s\n",__LINE__,errmsg);sqlite3_free(errmsg);return -1;}int nume=-1;while(1){system("clear");printf("*************学生管理系统***************\n");printf("***********1、添加学生信息**************\n");printf("***********2、删除学生信息**************\n");printf("***********3、修改学生信息**************\n");printf("***********4、查找学生信息**************\n");printf("***********0、退出管理系统**************\n");printf("输入选项:");scanf("%d",&nume);getchar();switch(nume){case 1:do_add(ppDb);break;case 2:do_delete(ppDb);break;case 3:do_update(ppDb);break;case 4:do_search(ppDb);break;case 0:exit(EXIT_SUCCESS);}while(getchar()!='\n');}sqlite3_close(ppDb);return 0;
}

三、牛客网刷题