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In this chapter, we will see a quick sample with basic functionalities of QxOrm library.

Note : QxOrm library uses the following syntax and naming convention for C++ source code :
  • all classes, functions, properties, etc... are defined under namespace qx ;
  • all macros of QxOrm library are prefixed by QX_... ;
  • all abstracts classes (or interfaces) start with prefix Ix (for example IxFactory is an interface to create an instance of object) ;
  • other classes start with prefix Qx (for example QxDataMember) ;
  • containers of objects end with suffix X (for example QxDataMemberX is a list of QxDataMember) ;
  • functions to interact with databases are under namespace qx::dao (for example qx::dao::fetch_by_id()) ;
  • functions to serialize are under namespace qx::serialization (for example qx::serialization::xml::to_file()) ;
  • the reflection (or introspection) engine can be used with qx::QxClassX (for example qx::QxClassX::invoke() to call a class method) ;
  • all traits classes are under namespace qx::trait (for example qx::trait::is_smart_ptr<T>).
QxOrm library has been accepted into the Qt Ambassador Program
Additional note : you can find a more complex sample (with inheritance, polymorphism, relationships, collections, shared libraries, memory leak, etc...) in the folder ./test/qxDllSample/ of your QxOrm package. The ./test/qxDllSample/ folder contains 2 projects of DLL type (shared libraries) and 1 project of executable type : ./dll1/, ./dll2/ and ./exe/.
This solution can be built with Visual C++ 2008, 2010 or 2012 on Windows (open the file ./test/qxDllSample/test.sln).
This solution can also be compiled with GCC on Linux, Clang on Mac OS X and MinGW on Windows with qmake command line.

Quick sample step by step :
* -----------------------------------------------------------------------------------------------------
* 1- drug.h file : drug class definition with 3 properties : id, name and description
* -----------------------------------------------------------------------------------------------------

#ifndef _CLASS_DRUG_H_
#define _CLASS_DRUG_H_

class drug
   long id;
   QString name;
   QString description;

   drug() : id(0) { ; }
   virtual ~drug() { ; }

QX_REGISTER_HPP_MY_TEST_EXE(drug, qx::trait::no_base_class_defined, 1)

/* This macro is necessary to register 'drug' class in QxOrm context */
/* param 1 : the current class to register => 'drug' */
/* param 2 : the base class, if no base class, use the qx trait => 'qx::trait::no_base_class_defined' */
/* param 3 : the class version used by serialization to provide 'ascendant compatibility' */

#endif // _CLASS_DRUG_H_

* ----------------------------------------------------------------------------------------------------
* 2- drug.cpp file : 'setting function' implementation : void qx::register_class()
* ----------------------------------------------------------------------------------------------------

#include "precompiled.h"   // Precompiled-header with '#include <QxOrm.h>' and '#include "export.h"'
#include "drug.h"          // Class definition 'drug'
#include <QxOrm_Impl.h>     // Automatic memory leak detection and boost serialization export macro

QX_REGISTER_CPP_MY_TEST_EXE(drug)   // This macro is necessary to register 'drug' class in QxOrm context

namespace qx {
template <> void register_class(QxClass<drug> & t)
  t.id(& drug::id, "id");               // Register 'drug::id' <=> primary key in your database
  t.data(& drug::name, "name", 1);      // Register 'drug::name' property with key 'name' and version '1'
  t.data(& drug::description, "desc");  // Register 'drug::description' property with key 'desc'

* -----------------------------------------------------------------------------------------------
* 3- main.cpp file : basic functionalities of QxOrm library with drug class
* -----------------------------------------------------------------------------------------------

#include "precompiled.h"
#include "drug.h"
#include <QxOrm_Impl.h>

int main(int argc, char * argv[])
   QApplication app(argc, argv); // Qt application

   // Create 3 new drugs
   // It is possible to use 'boost' and 'Qt' smart pointer : 'boost::shared_ptr', 'QSharedPointer', etc...
   typedef boost::shared_ptr<drug> drug_ptr;
   drug_ptr d1; d1.reset(new drug()); d1->name = "name1"; d1->description = "desc1";
   drug_ptr d2; d2.reset(new drug()); d2->name = "name2"; d2->description = "desc2";
   drug_ptr d3; d3.reset(new drug()); d3->name = "name3"; d3->description = "desc3";

   // Insert drugs into container
   // It is possible to use many containers from 'std', 'boost', 'Qt' and 'qx::QxCollection<Key, Value>'
   typedef std::vector<drug_ptr> type_lst_drug;
   type_lst_drug lst_drug;

   // Init parameters to communicate with a database

   // Create table 'drug' into database to store drugs
   QSqlError daoError = qx::dao::create_table<drug>();

   // Insert drugs from container to database
   // 'id' property of 'd1', 'd2' and 'd3' are auto-updated
   daoError = qx::dao::insert(lst_drug);

   // Modify and update the second drug into database
   d2->name = "name2 modified";
   d2->description = "desc2 modified";
   daoError = qx::dao::update(d2);

   // Delete the first drug from database
   daoError = qx::dao::delete_by_id(d1);

   // Count drugs into database
   long lDrugCount = qx::dao::count<drug>();

   // Fetch drug with id '3' into a new variable
   drug_ptr d_tmp; d_tmp.reset(new drug());
   d_tmp->id = 3;
   daoError = qx::dao::fetch_by_id(d_tmp);

   // Export drugs from container to a file under xml format (serialization)
   qx::serialization::xml::to_file(lst_drug, "./export_drugs.xml");

   // Import drugs from xml file into a new container
   type_lst_drug lst_drug_tmp;
   qx::serialization::xml::from_file(lst_drug_tmp, "./export_drugs.xml");

   // Clone a drug
   drug_ptr d_clone = qx::clone(* d1);

   // Create a new drug by class name (factory)
   boost::any d_any = qx::create("drug");

   // Insert drugs container into 'qx::cache'
   qx::cache::set("drugs", lst_drug);

   // Remove all elements from 'qx::cache'

   // Create a dummy memory leak
   drug * pDummy = new drug();

   return 0;

* -------------------------------------------------------------------------
* 4- execute program and trace output debug
* -------------------------------------------------------------------------

[QxOrm] qx::QxSqlDatabase : create new database connection in thread '3616' with key '{d315250c-b5c9-46e0-9402-f800368a6673}'
[QxOrm] sql query (63 ms) : INSERT INTO drug (name, desc) VALUES (:name, :desc)
[QxOrm] sql query (62 ms) : UPDATE drug SET id = :id, name = :name, desc = :desc WHERE id = :id_bis
[QxOrm] sql query (63 ms) : DELETE FROM drug WHERE id = :id
[QxOrm] sql query (0 ms) : SELECT COUNT(*) FROM drug
[QxOrm] sql query (0 ms) : SELECT drug.id AS drug_id_0, drug.name AS drug_name_0, drug.desc AS drug_desc_0 FROM drug WHERE drug_id_0 = :id
[QxOrm] Leaked object at 0xf52ad8 (size 16, src\main.cpp:74)
[QxOrm] **** 1 memory leaks found ****

* ------------------------------------------------------------------------------
* 5- ./export_drugs.xml file created by the program
* ------------------------------------------------------------------------------


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