[sqlite] Why can't I delete tmp.db after close sqlite?

[LuYanJun]

Hi all
Why can't I delete tmp.db after close sqlite?
 
sqlite3* mpDB;
  int nRet = sqlite3_open("tmp.db", &mpDB);
  if (nRet != SQLITE_OK)
  {
   const char* szError = sqlite3_errmsg(mpDB);
   printf("open error:%s\n",szError);
  }
  sqlite3_close(mpDB);
  printf("close!\n");
  if ( ! ::DeleteFile(tmp.db ))
  {
   printf("delete error!\n");
  }
  else
   printf("ok delete!!!\n");
  return 0; 

Best regards