/* Database Manage System */
#include <stdio.h>
#include <stdlib.h>
#include <conio.h>
#include <string.h>
#define MAX_SIZE 50 /*表中所含字段最大长度*/
#define FILE_NAME_LENGTH 15 /*文件名最大长度*/
#define FIELD_NAME_LENGTH 15 /*字段名最大长度*/
#define T_EDIT_LENGTH 15 /* Table Edit 长度*/
typedef struct {
char sFieldName[FIELD_NAME_LENGTH]; /*列名*/
char sType[8]; /*列类型*/
int iSize; /*列空间大小*/
char bKey; /*是否主键*/
char bNullFlag; /*是否为空*/
char bValidFlag; /*是否有效 */
} TableMode,*PTableMode;
void main()
{
TableMode tempTM; /*临时文件*/
TableMode FieldSet[MAX_SIZE];
int bFound; /* found the table */
FILE *fp,*tempfp; /*定义文件指针*/
int tempi,tempi1,tempiNum,iNum,jNum; /*iNum is the number of the Field,and jNum is Record */
char tempc,temps[FILE_NAME_LENGTH],*temps1;
char recordset[2*MAX_SIZE][FILE_NAME_LENGTH];
char dbf[FILE_NAME_LENGTH];
char datf[FILE_NAME_LENGTH];
char tname[FILE_NAME_LENGTH];
char temptn[FILE_NAME_LENGTH]; /* 数据库文件名dbf，表名tname */
char ctemp_edit[15][15],*c; /*edit语句的中间变量存放数组*/
char ctable_name[10];
int size_edit; /*Size*/
char key_edit; /*Key*/
char null_edit; /*Null*/
char valid_edit; /*Valid*/
char dbfile[15];
int i=0,j=0,k=0;
FILE *fp_edit;
int success=0;
static int s; /*size*/
static char ke,n,v; /*key,null,valid*/
int y=0;
char inssql[15][15];
int icd=0;
char again;
int temp=0;
char datafile[15];
int flag=0,sFieldNameFlag=0;
int t=0;
int r=0;
char code[6];
int login=0;
strcpy(dbfile,"edit.tmp") ;
strcpy(datafile,"data.tmp");
printf("
---------------SQL For DBMS---------------------
");
printf("
------------Please LogIN The DBMS--------------");
for(i=0;i<5;i++)
{
printf("
LOG>Password:");
scanf("%s",code);
if(strcmp(code,"admin")==0)
{
printf("
Log in Database Manage System Suceess!
");
login=1;
break;
}
else
{
printf("
LOG>Wrong Password!
");
login=0;
}
}
printf("Please input the datafile name:");
scanf("%s",datf);
while(login)
{
iNum=0; /*iNum置0*/
printf("
SQL>");
scanf("%s",ctemp_edit[0]);
switch(ctemp_edit[0][0])
{
case 'c': /* 创建新表 */
if (strcmp(ctemp_edit[0],"create")==0) printf("");
else { printf("Wrong SQL!
");break;}
scanf("%s",ctemp_edit[1]); /* table */
scanf("%15s",ctemp_edit[2]); /*表名*/
scanf("%s",ctemp_edit[3]); /* ( */
do{
scanf("%15s",ctemp_edit[4]); /*字段名*/
scanf("%8s",ctemp_edit[5]); /*类型*/
scanf("%d",&size_edit); /*大小*/
scanf("%c",&key_edit);
while(key_edit==' ')
scanf("%c",&key_edit); /*主键*/
scanf("%c",&null_edit);
while(null_edit==' ')
scanf("%c",&null_edit); /*空值*/
scanf("%c",&valid_edit);
while(valid_edit==' ')
scanf("%c",&valid_edit); /*可视化 一般为y*/
strcpy(tempTM.sFieldName,ctemp_edit[4]); /*列名*/
strcpy(tempTM.sType,ctemp_edit[5]); /* 列类型 */
tempTM.iSize=size_edit; /* 大小 */
tempTM.bKey=key_edit; /* 主键 */
tempTM.bNullFlag=null_edit; /* 值是否为空 */
tempTM.bValidFlag=valid_edit; /* 该字段是否有效，这里默认为有效*/
FieldSet[iNum]=tempTM; /*将tempTM放入FieldSet数组内*/
iNum++; /*iNum加1*/
scanf("%c",&again);
while(again==' ')
scanf("%c",&again);
}while(again==',');
scanf("%s",ctemp_edit[11]); /* INTO */
scanf("%s",ctemp_edit[12]); /* DataBase_FileName */
if (strcmp(ctemp_edit[1],"table")==0) printf("");
else{ printf(" table ERROR !!!
");break;}
if(strcmp(ctemp_edit[3],"(")==0) printf("");
else { printf(" ( ERROR
"); break;}
if(again==')') printf("");
else { printf(" ) ERROR !!!
"); break;}
if(strcmp(ctemp_edit[11],"into")==0) printf("");
else { printf(" into error!!!
"); break;}
if((fp=fopen(ctemp_edit[12],"ab+")) == NULL )
{
printf("
open or create file error!!!
" );
getch();
exit(1);
}
fwrite("~",sizeof(char),1,fp);
fwrite(ctemp_edit[2],sizeof(char),FILE_NAME_LENGTH,fp);
fwrite(&iNum,sizeof(int),1,fp); /*此表内所含字段结构的数量*/
fwrite(FieldSet,sizeof(TableMode),iNum,fp); /*表的字段结构*/
fclose(fp); /*关闭文件*/
printf("
Table Create Successfully!");
break;
case 'v': /* 看表 */
if (strcmp(ctemp_edit[0],"view")==0) printf("");
else { printf("Wrong SQL!
");break;}
scanf("%s",ctemp_edit[1]); /*读入table*/
scanf("%s",ctemp_edit[2]); /*读入表名*/
scanf("%s",ctemp_edit[3]); /*读入in*/
scanf("%s",dbf); /*读入文件名*/
if (strcmp(ctemp_edit[1],"table")==0)
printf("");
else{ printf(" table ERROR !!!
");break;}
if (strcmp(ctemp_edit[3],"in")==0)
printf("");
else{ printf(" in ERROR !!!
");break;}
if((fp=fopen(dbf,"rb")) == NULL )
{
printf("
File Not Exist or Bad File!
" );
break;
}
if(strcmp(ctemp_edit[2],"*")==0)
{
printf("
Tables in %s are as following:",dbf);
while(!feof(fp))
{
tempi=fread(&tempc,sizeof(char),1,fp);
if(!tempi)break;
if(tempc!='~')
{
printf("
%s Database Format NOT correct!",dbf);
fclose(fp);
exit(1);
}
fread(tname,sizeof(char),FILE_NAME_LENGTH,fp);
fread(&iNum,sizeof(int),1,fp);
printf("
%s",tname);
fread(FieldSet,sizeof(TableMode),iNum,fp);
}
break;
}
else
{
while(!feof(fp))
{ /*输出表所有字段 */
bFound=0;
tempi=fread(&tempc,sizeof(char),1,fp);
if(!tempi)
break;
fread(temptn,sizeof(char),FILE_NAME_LENGTH,fp);
fread(&iNum,sizeof(int),1,fp);
fread(FieldSet,sizeof(TableMode),iNum,fp);
if(strcmp(ctemp_edit[2],temptn)==0)
{
printf("
Found! Table Fields are as following:");
printf("
Field Name Type Size Key Null");
printf("
------------ ------ ---- ---- ---- ");
for(tempi=0;tempi<iNum;tempi++)
printf("
%-15s|%-8s|%-5d|%-5c|%-5c|",FieldSet[tempi].sFieldName,FieldSet[tempi].sType,FieldSet[tempi].iSize,FieldSet[tempi].bKe
到此这篇增删改查sql语句问题与解决（增、删、改、查 对应的sql语法）的文章就介绍到这了,更多相关 内容请继续浏览下面的相关 推荐文章，希望大家都能在编程的领域有一番成就！版权声明：
本文来自互联网用户投稿，该文观点仅代表作者本人，不代表本站立场。本站仅提供信息存储空间服务，不拥有所有权，不承担相关法律责任。
如若内容造成侵权、违法违规、事实不符，请将相关资料发送至xkadmin@xkablog.com进行投诉反馈，一经查实，立即处理！
转载请注明出处，原文链接：https://www.xkablog.com/sqlbc/61124.html