新建 文本文档 (2).txt

sqlite 3.0使用方法

下面是主函数：
// TestBerkeleyDB.cpp : Defines the entry point for the console application.

#include "stdafx.h"
#include "TestBerkeleyDB.h"
#include "db_cxx.h"
#include "icqtypes.h"
#include "icqdb.h"
#include "Person.h"

#ifdef _DEBUG
#define new DEBUG_NEW
#undef THIS_FILE
static char THIS_FILE[] = __FILE__;
#endif

/////////////////////////////////////////////////////////////////////////////
// The one and only application object

CWinApp theApp;

//using namespace std;

bool delPeople(char *fileName, string index)
{
 Db db(NULL, 0); // Instantiate the Db object
 u_int32_t oFlags = DB_CREATE; // Open flags;
 try {
 // Open the database
 db.open(NULL, // Transaction pointer
   fileName, // Database file name
   NULL, // Optional logical database name
   DB_BTREE, // Database access method
   oFlags, // Open flags
   0); // File mode (using defaults)
   // DbException is not subclassed from std::exception, so
   // need to catch both of these.
  } catch(DbException &e) {
  // Error handling code goes here
  } catch(std::exception &e) {
  // Error handling code goes here
  }
 Dbc *cursorp;
 try {
  // Database open omitted
  // Get the cursor
  db.cursor(NULL, &cursorp, 0);
  // Set up our DBTs
  Dbt data;
  Dbt key;
  key.set_data((void*)index.c_str());
  key.set_size(index.length()+1);
  
  // Iterate over the database, deleting each record in turn.
  int ret;
  while ((ret = cursorp->get(&key, &data,
   DB_SET)) == 0) {
   cursorp->del(0);
  }
 } catch(DbException &e) {
  db.err(e.get_errno(), "Error!");
 } catch(std::exception &e) {
  db.errx("Error! %s", e.what());
 }
  // Cursors must be closed
 if (cursorp != NULL)
   cursorp->close();
 db.close(0);
 return true;
}

bool delPeople(char *fileName, uint32 index)
{
 Db db(NULL, 0); // Instantiate the Db object
 u_int32_t oFlags = DB_CREATE; // Open flags;
 try {
  // Open the database
  db.open(NULL, // Transaction pointer
   fileName, // Database file name
   NULL, // Optional logical database name
   DB_BTREE, // Database access method
   oFlags, // Open flags
   0); // File mode (using defaults)
  // DbException is not subclassed from std::exception, so
  // need to catch both of these.
 } catch(DbException &e) {
  // Error handling code goes here
 } catch(std::exception &e) {
  // Error handling code goes here
 }
 Dbc *cursorp;
 try {
  // Database open omitted
  // Get the cursor
  db.cursor(NULL, &cursorp, 0);
  // Set up our DBTs
  Dbt data;
  Dbt key;
  key.set_data(&index);
  key.set_size(sizeof(index));
  
  // Iterate over the database, deleting each record in turn.
  int ret;
  while ((ret = cursorp->get(&key, &data,
   DB_SET)) == 0) {
   cursorp->del(0);
  }
 } catch(DbException &e) {
  db.err(e.get_errno(), "Error!");
 } catch(std::exception &e) {
  db.errx("Error! %s", e.what());
 }
 // Cursors must be closed
 if (cursorp != NULL)
  cursorp->close();
 db.close(0);
 return true;
}

bool loadPeople(char *fileName, uint32 index, DBSerialize &obj)
{
 Db db(NULL, 0); // Instantiate the Db object
 u_int32_t oFlags = DB_CREATE; // Open flags;
 try {
 // Open the database
 db.open(NULL, // Transaction pointer
    fileName, // Database file name
    NULL, // Optional logical database name
    DB_BTREE, // Database access method
    oFlags, // Open flags
    0); // File mode (using defaults)
    // DbException is not subclassed from std::exception, so
    // need to catch both of these.
    } catch(DbException &e) {
    // Error handling code goes here
    } catch(std::exception &e) {
    // Error handling code goes here
    }

 Dbt key, data;
 key.set_data(&index);
 key.set_size(sizeof(index));

 if (db.get(NULL, &key, &data, 0) != 0) {
  db.close(0);
  return false;
 }

 DBInStream in(data.get_data(), data.get_size());
 obj.load(in);

 db.close(0);
 return true;
}

bool loadPeople(char *fileName, string index, DBSerialize &obj)
{
 Db db(NULL, 0); // Instantiate the Db object
 u_int32_t oFlags = DB_CREATE; // Open flags;
 try {
 // Open the database
 db.open(NULL, // Transaction pointer
    fileName, // Database file name
    NULL, // Optional logical database name
    DB_BTREE, // Database access method
    oFlags, // Open flags
    0); // File mode (using defaults)
    // DbException is not subclassed from std::exception, so
    // need to catch both of these.
    } catch(DbException &e) {
    // Error handling code goes here
    } catch(std::exception &e) {
    // Error handling code goes here
    }

 Dbt key, data;
 key.set_data((void*)index.c_str());
 key.set_size(index.length()+1);

 if (db.get(NULL, &key, &data, 0) != 0) {
  db.close(0);
  return false;
 }

 DBInStream in(data.get_data(), data.get_size());
 obj.load(in);

 db.close(0);
 return true;
}

bool savePeople(char *fileName, uint32 index, DBSerialize &obj)
{
 Db db(NULL, 0); // Instantiate the Db object
 u_int32_t oFlags = DB_CREATE; // Open flags;
 try {
 // Open the database
 db.open(NULL, // Transaction pointer
    fileName, // Database file name
    NULL, // Optional logical database name
    DB_BTREE, // Database access method
    oFlags, // Open flags
    0); // File mode (using defaults)
    // DbException is not subclassed from std::exception, so
    // need to catch both of these.
    } catch(DbException &e) {
    // Error handling code goes here
    } catch(std::exception &e) {
    // Error handling code goes here
    }
    
 DBOutStream out;
 obj.save(out);

 Dbt key, data;
 key.set_data(&index);
 key.set_size(sizeof(index));
 data.set_data(out.getData());
 data.set_size(out.getSize());
 int ret = db.put(NULL, &key, &data, 0) ;
 db.close(0);
 return (ret == 0);
}

bool savePeople(char *fileName, string index, DBSerialize &obj)
{
 Db db(NULL, 0); // Instantiate the Db object
 u_int32_t oFlags = DB_CREATE; // Open flags;
 try {
 // Open the database
 db.open(NULL, // Transaction pointer
    fileName, // Database file name
    NULL, // Optional logical database name
    DB_BTREE, // Database access method
    oFlags, // Open flags
    0); // File mode (using defaults)
    // DbException is not subclassed from std::exception, so
    // need to catch both of these.
    } catch(DbException &e) {
    // Error handling code goes here
    } catch(std::exception &e) {
    // Error handling code goes here
    }   
 DBOutStream out;
 obj.save(out);

 Dbt key, data;
 key.set_data((void*)index.c_str());
 key.set_size(index.length()+1);
 data.set_data(out.getData());
 data.set_size(out.getSize());
 int ret = db.put(NULL, &key, &data, 0);
 db.close(0);
 return (ret == 0);
}

bool printAllPeople(char *fileName)
{
 Db db(NULL, 0); // Instantiate the Db object
 u_int32_t oFlags = DB_CREATE; // Open flags;
 try {
  // Open the database
  db.open(NULL, // Transaction pointer
   fileName, // Database file name
   NULL, // Optional logical database name
   DB_BTREE, // Database access method
   oFlags, // Open flags
   0); // File mode (using defaults)
  // DbException is not subclassed from std::exception, so
  // need to catch both of these.
 } catch(DbException &e) {
  // Error handling code goes here
 } catch(std::exception &e) {
  // Error handling code goes here
 }
 Dbc *cursorp;
 try {
  // Database open omitted
  // Get the cursor
  db.cursor(NULL, &cursorp, 0);
  // Set up our DBTs
  Dbt data;
  Dbt key;
  // Iterate over the database, deleting each record in turn.
  int ret;
  while ((ret = cursorp->get(&key, &data,
   DB_NEXT)) == 0) {
   //cursorp->del(0);
   CPerson p;
   DBInStream in(data.get_data(), data.get_size());
   p.load(in);
   printf("%s\n",p.Describe);

  }
 } catch(DbException &e) {
  db.err(e.get_errno(), "Error!");
 } catch(std::exception &e) {
  db.errx("Error! %s", e.what());
 }
 // Cursors must be closed
 if (cursorp != NULL)
  cursorp->close();
 db.close(0);
 return true;
}

int _tmain(int argc, TCHAR* argv[], TCHAR* envp[])
{
 int nRetCode = 0;

 // initialize MFC and print and error on failure
 if (!AfxWinInit(::GetModuleHandle(NULL), NULL, ::GetCommandLine(), 0))
 {
  // TODO: change error code to suit your needs
  cerr << _T("Fatal Error: MFC initialization failed") << endl;
  nRetCode = 1;
 }
 else
 {
  string index1 = "Liang Zhijian";
  string index2 = "Zou Dan";
  CPerson p1;
  p1.age = 0;
  p1.Name = "Liang Zhijian";
  p1.Describe = "student1";

  savePeople("mydb.db",index1,p1);

  CPerson p2;
  p2.age = 1;
  p2.Name = "Zou Dan";
  p2.Describe = "student2"; 
  savePeople("mydb.db",index2,p2);

  CPerson p3;
  loadPeople("mydb.db","Liang Zhijian",p3);
  printf("%s\n",p3.Describe);
  
  printAllPeople("mydb.db");
  delPeople("mydb.db","Liang Zhijian");
  printAllPeople("mydb.db");
 }
 
 return nRetCode;
}