练习：
1> 创建一个工人信息库，包含工号（主键）、姓名、年龄、薪资。
2> 添加三条工人信息（可以完整信息，也可以非完整信息）
3> 修改某一个工人的薪资（确定的一个）
4> 展示出工资在10000到20000之间的所有工人信息
5> 删除掉指定姓名工人的信息
6> 删除工人信息库
#include<myhead.h>
#include<sqlite3.h>
sqlite3 * creat_sqlite() //创建数据库并返回数据库句柄
{
const char *p = "./my.db";
sqlite3 *ppDb;
if(sqlite3_open(p,&ppDb)!=SQLITE_OK) //调用数据库提供的第三方库函数
{
printf("打开数据库失败\n");
printf("%s\n",sqlite3_errmsg(ppDb)); //错误信息
printf("%d\n",sqlite3_errcode(ppDb)); //错误码
printf("sqlite3_open");
}
return ppDb; //返回数据库句柄
}
void insert_worker(sqlite3 *ppDb) //插入员工信息
{
char sql[1024];
char *errmsg; //存储错误信息的指针
sprintf(sql,"%s","create table worker(num int primary key,name char,age int,salary int);");
if(sqlite3_exec(ppDb,sql,NULL,NULL,&errmsg)!=SQLITE_OK)
{
printf("%s\n",sqlite3_errmsg(ppDb)); //错误信息
printf("%d\n",sqlite3_errcode(ppDb)); //错误码
}
printf("创建表格成功\n");
int num;
char name[100];
int age;
int salary;
printf("请输入你要添加的工人信息:\n");
scanf("%d %s %d %d",&num,name,&age,&salary);
getchar();
snprintf(sql,sizeof(sql),"insert into worker values(%d,\"%s\",%d,%d);",num,name,age,salary);
if(sqlite3_exec(ppDb,sql,NULL,NULL,&errmsg)!=SQLITE_OK)
{
printf("%s\n",sqlite3_errmsg(ppDb)); //错误信息
printf("%d\n",sqlite3_errcode(ppDb)); //错误码
}
printf("添加成功\n");
}
void update_worker(sqlite3 *ppDb)
{
int num;
int salary;
char * errmsg;
char sql[1024];
printf("请输入你要修改的工人的工号：\n");
scanf("%d",&num);
getchar();
printf("请你输入改的值：\n");
scanf("%d",&salary);
getchar();
snprintf(sql,sizeof(sql),"update worker set salary=%d where num=%d",salary,num);
if(sqlite3_exec(ppDb,sql,NULL,NULL,&errmsg)!=SQLITE_OK)
{
printf("%s\n",sqlite3_errmsg(ppDb));
printf("%d\n",sqlite3_errcode(ppDb));
}
printf("修改成功\n");
}
void show(sqlite3 *ppDb)
{
char sql[1024];
char * errmsg;
int salary;
const char *sq = "select * from worker where salary>10000 and salary<20000";
sqlite3_stmt *stmt;
snprintf(sql,sizeof(sql),"select * from worker where salary>10000 and salary<20000");
if(sqlite3_exec(ppDb,sql,NULL,NULL,&errmsg)!=SQLITE_OK)
{
printf("%s\n",sqlite3_errmsg(ppDb));
printf("%d\n",sqlite3_errcode(ppDb));
}
int res = sqlite3_prepare_v2(ppDb,sq,-1,&stmt,NULL);
printf("工资在10000到20000的工人:\n");
while((res = sqlite3_step(stmt))==SQLITE_ROW)
{
printf("num = %d,name = %s,age = %d,salary = %d\n",
sqlite3_column_int(stmt,0),
sqlite3_column_text(stmt,1),
sqlite3_column_int(stmt,2),
sqlite3_column_int(stmt,3));
}
sqlite3_finalize(stmt);
}
void delete_worker(sqlite3 *ppDb)
{
char name[20];
char * errmsg;
char sql[1024];
printf("请输入你要删除的工人的姓名：\n");
scanf("%s",name);
getchar();
snprintf(sql,sizeof(sql),"delete from worker where name = '%s' ",name);
if(sqlite3_exec(ppDb,sql,NULL,NULL,&errmsg)!=SQLITE_OK)
{
printf("%s\n",sqlite3_errmsg(ppDb));
printf("%d\n",sqlite3_errcode(ppDb));
}
printf("删除成功\n");
}
void delete(sqlite3 *ppDb)
{
char name[20];
char * errmsg;
char sql[1024];
snprintf(sql,sizeof(sql),"drop table worker ");
if(sqlite3_exec(ppDb,sql,NULL,NULL,&errmsg)!=SQLITE_OK)
{
printf("%s\n",sqlite3_errmsg(ppDb));
printf("%d\n",sqlite3_errcode(ppDb));
}
printf("删除成功\n");
}
void menu()
{
int ch;
sqlite3 *ppDb;
while(1)
{
printf("\t\t\t1、创建数据库\n");
printf("\t\t\t2、添加工人信息\n");
printf("\t\t\t3、修改工人信息\n");
printf("\t\t\t4、展示所有信息\n");
printf("\t\t\t5、删除指定工人信息\n");
printf("\t\t\t6、删除整表\n");
printf("\t\t\t0、退出\n");
printf("请输入你的选择：");
scanf("%d",&ch);
getchar();
switch(ch)
{
case 1:
{
ppDb = creat_sqlite();
}
break;
case 2:
{
insert_worker(ppDb);
}
break;
case 3:
{
update_worker(ppDb);
}
break;
case 4:
{
show(ppDb);
}
break;
case 5:
{
delete_worker(ppDb);
}
break;
case 6:
{
delete(ppDb);
}
break;
case 0:
exit(0);
break;
default:
printf("输入错误，请重新输入\n");
}
}
}
int main(int argc, const char *argv[])
{
menu(); //调用菜单函数
return 0;
}