demo3.cpp
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- /*
- * ===========================================================================
- * PRODUCTION $Log: demo3.cpp,v $
- * PRODUCTION Revision 1000.1 2004/06/01 18:37:48 gouriano
- * PRODUCTION PRODUCTION: UPGRADED [GCC34_MSVC7] Dev-tree R1.3
- * PRODUCTION
- * ===========================================================================
- */
- /* $Id: demo3.cpp,v 1000.1 2004/06/01 18:37:48 gouriano Exp $
- * ===========================================================================
- *
- * PUBLIC DOMAIN NOTICE
- * National Center for Biotechnology Information
- *
- * This software/database is a "United States Government Work" under the
- * terms of the United States Copyright Act. It was written as part of
- * the author's official duties as a United States Government employee and
- * thus cannot be copyrighted. This software/database is freely available
- * to the public for use. The National Library of Medicine and the U.S.
- * Government have not placed any restriction on its use or reproduction.
- *
- * Although all reasonable efforts have been taken to ensure the accuracy
- * and reliability of the software and data, the NLM and the U.S.
- * Government do not and cannot warrant the performance or results that
- * may be obtained by using this software or data. The NLM and the U.S.
- * Government disclaim all warranties, express or implied, including
- * warranties of performance, merchantability or fitness for any particular
- * purpose.
- *
- * Please cite the author in any work or product based on this material.
- *
- * ===========================================================================
- *
- * Author: Anatoliy Kuznetsov
- *
- * File Description: Demo3 application for NCBI Berkeley DB library (BDB).
- * Shows how to create additional BTree index file to
- * improve search performance.
- *
- */
- #include <ncbi_pch.hpp>
- #include <corelib/ncbiapp.hpp>
- #include <corelib/ncbiargs.hpp>
- #include <bdb/bdb_cursor.hpp>
- #include <assert.h>
- #include <list>
- USING_NCBI_SCOPE;
- //////////////////////////////////////////////////////////////////
- //
- // Structure implements database table record in "phone book"
- // database table.
- //
- //
- struct SPhoneBookDB : public CBDB_File
- {
- CBDB_FieldInt4 person_id;
- CBDB_FieldString first_name;
- CBDB_FieldString last_name;
- CBDB_FieldInt4 zip_code;
- CBDB_FieldString phone;
- // Constructor binds field variables.
- SPhoneBookDB()
- {
- // Bind int primary key. Cannot be NULL.
- BindKey("PersonId", &person_id);
- // Bind non-PK data fields
- BindData("FirstName", &first_name, 64, eNotNullable);
- BindData("LastName", &last_name, 64, eNotNullable);
- BindData("Zip", &zip_code); // NULLable by default
- BindData("Phone", &phone, 32); // NULLable by default
- }
- };
- const char* s_PhoneBookDBFileName = "phone.db";
- //////////////////////////////////////////////////////////////////
- //
- // Structure implements index record for "phone book"
- // database table. BTree index stores Zip code and correspondent
- // primary key in the main table.
- //
- struct SPhoneBookZipIDX : public CBDB_File
- {
- CBDB_FieldInt4 zip_code;
- CBDB_FieldInt4 person_id;
- SPhoneBookZipIDX()
- {
- BindKey("Zip", &zip_code);
- BindKey("PersonId", &person_id);
- }
- };
- const char* s_PhoneBookZipIDXFileName = "phone_zip.idx";
- void LoadPhoneBook()
- {
- SPhoneBookDB dbf;
- dbf.Open(s_PhoneBookDBFileName, CBDB_File::eCreate);
-
- dbf.person_id = 1;
- dbf.first_name = "John";
- dbf.last_name = "Doe";
- dbf.zip_code = 10785;
- dbf.phone = "+1(240)123456";
-
- EBDB_ErrCode ret = dbf.Insert();
- // Check Insert result, it can be 'eBDB_KeyDup'
- // if primary key already exists
- if (ret != eBDB_Ok) {
- cout << "Insert failed!" << endl;
- exit(1);
- }
-
- dbf.person_id = 2;
- dbf.first_name = "Antony";
- dbf.last_name = "Smith";
- dbf.zip_code = 10785;
- dbf.phone = "(240)234567";
- ret = dbf.Insert();
- if (ret != eBDB_Ok) {
- cout << "Insert failed!" << endl;
- exit(1);
- }
- dbf.person_id = 3;
- dbf.first_name = "John";
- dbf.last_name = "Public";
- dbf.zip_code = 40000;
-
- ret = dbf.Insert();
- if (ret != eBDB_Ok) {
- cout << "Insert failed!" << endl;
- exit(1);
- }
- }
- //
- // Function builds Zip code index.
- // Indexing procedure creates a cursor on the main data file, fetches all data
- // and adds corresponding entries to the index. From the technical standpoint
- // both data and index are both BTree Berkeley DB files.
- //
- void BuildZipIndex(SPhoneBookDB& dbf)
- {
- SPhoneBookZipIDX idx;
- idx.Open(s_PhoneBookZipIDXFileName, CBDB_File::eCreate);
- CBDB_FileCursor cur(dbf);
- cur.SetCondition(CBDB_FileCursor::eFirst);
- while (cur.Fetch() == eBDB_Ok) {
- if (dbf.zip_code.IsNull()) // NULL values are dropped
- continue;
-
- idx.zip_code = dbf.zip_code;
- idx.person_id = dbf.person_id;
- EBDB_ErrCode ret = idx.Insert();
- if (ret != eBDB_Ok) {
- cout << "Insert failed!" << endl;
- exit(1);
- }
- }
- }
- // Function prints the database record.
- void PrintRecord(const SPhoneBookDB& rec)
- {
- cout << rec.person_id.GetName() << ": " << rec.person_id.Get() << endl;
- cout << rec.first_name.GetName()<< ": ";
- if (rec.first_name.IsNull()) {
- cout << "NULL" << endl;
- } else {
- cout << (const char*) rec.first_name << endl;
- }
- cout << rec.last_name.GetName()<< ": ";
- if (rec.last_name.IsNull()) {
- cout << "NULL" << endl;
- } else {
- cout << (const char*) rec.last_name << endl;
- }
- cout << rec.zip_code.GetName()<< ": ";
- if (rec.zip_code.IsNull()) {
- cout << "NULL" << endl;
- } else {
- cout << (Int4) rec.zip_code << endl;
- }
- cout << rec.phone.GetName()<< ": ";
- if (rec.phone.IsNull()) {
- cout << "NULL" << endl;
- } else {
- cout << (const char*) rec.phone << endl;
- }
- }
- //
- // Search function uses Zip code index for fast data retrieval.
- // Actual data seach is two phase process.
- // First we seach the index values and collect the parent table primary key.
- // Then we go and get the primary data table records.
- //
- void SearchPhoneBook(SPhoneBookDB& dbf, SPhoneBookZipIDX& idx, int zip_code)
- {
- list<int> person_id;
- // Index search. Here we store seach values in the list.
- {{
- CBDB_FileCursor cur(idx);
- cur.SetCondition(CBDB_FileCursor::eEQ);
- cur.From << zip_code;
- while (cur.Fetch() == eBDB_Ok) {
- person_id.push_back(idx.person_id.Get());
- }
- }}
- if (person_id.empty()) {
- cout << "No records found." << endl;
- return;
- }
- // Data retrieval using index seach values.
- for (list<int>::const_iterator it = person_id.begin();
- it != person_id.end(); ++it) {
- dbf.person_id = *it;
- EBDB_ErrCode ret = dbf.Fetch();
- assert(ret == eBDB_Ok);
- cout << "====================================" << endl;
- PrintRecord(dbf);
- }
- }
- ////////////////////////////////
- // Demo3 application
- //
- class CBDB_PhoneBookDemo3 : public CNcbiApplication
- {
- public:
- void Init(void);
- int Run(void);
- };
- void CBDB_PhoneBookDemo3::Init(void)
- {
- SetDiagPostLevel(eDiag_Warning);
- SetDiagPostFlag(eDPF_File);
- SetDiagPostFlag(eDPF_Line);
- auto_ptr<CArgDescriptions> d(new CArgDescriptions);
- d->SetUsageContext("bdb demo3",
- "Demo3 application for BDB library");
- SetupArgDescriptions(d.release());
- }
- int CBDB_PhoneBookDemo3::Run(void)
- {
- try
- {
- LoadPhoneBook();
- SPhoneBookDB dbf;
- dbf.Open(s_PhoneBookDBFileName, CBDB_File::eReadOnly);
- BuildZipIndex(dbf);
- SPhoneBookZipIDX idx;
- idx.Open(s_PhoneBookZipIDXFileName, CBDB_File::eReadOnly);
- SearchPhoneBook(dbf, idx, 10785);
- }
- catch (CBDB_ErrnoException& ex)
- {
- cout << "Error! DBD errno exception:" << ex.what();
- return 1;
- }
- catch (CBDB_LibException& ex)
- {
- cout << "Error! DBD library exception:" << ex.what();
- return 1;
- }
- return 0;
- }
- int main(int argc, const char* argv[])
- {
- return CBDB_PhoneBookDemo3().AppMain(argc, argv, 0, eDS_Default, 0);
- }
- /*
- * ===========================================================================
- * $Log: demo3.cpp,v $
- * Revision 1000.1 2004/06/01 18:37:48 gouriano
- * PRODUCTION: UPGRADED [GCC34_MSVC7] Dev-tree R1.3
- *
- * Revision 1.3 2004/05/17 20:55:18 gorelenk
- * Added include of PCH ncbi_pch.hpp
- *
- * Revision 1.2 2003/05/02 16:23:14 kuznets
- * Cosmetic fixes
- *
- * Revision 1.1 2003/05/01 13:44:57 kuznets
- * Initial revision
- *
- * ===========================================================================
- */