| QxOrm 1.4.3 C++ Object Relational Mapping library

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QxOrm - C++ Object Relational Mapping library

QxOrm is a C++ library designed to provide Object Relational Mapping (ORM) feature to C++/Qt developers (like Hibernate in Java, or NHibernate in .Net).
QxOrm engine is based on a simple and non intrusive mapping function per class to provide :

- Persistence (based on QtSql Qt module) ;
- Serialization (XML and binary, based on Qt and boost serialization engines) ;
- Reflection or Introspection (invoke dynamically class methods and access to properties).

QxOrm is developed by Lionel Marty, a software development engineer since 2003.
QxOrm library has been accepted into the Qt Ambassador Program.

For more information about QxOrm library (quick sample, tutorial and forum), please visit : http://www.qxorm.com/.
A manual (user guide) to learn how to work with QxOrm library is available on QxOrm website.

## Quick sample using QxOrm library

1- drug.h file : drug class definition with 3 properties : id, name and description

    #ifndef _CLASS_DRUG_H_
    #define _CLASS_DRUG_H_

    class drug
    {
    public:
       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 a lot of containers from 'std', 'boost', 'Qt' and 'qx::QxCollection<Key, Value>'
       typedef std::vector<drug_ptr> type_lst_drug;
       type_lst_drug lst_drug;
       lst_drug.push_back(d1);
       lst_drug.push_back(d2);
       lst_drug.push_back(d3);

       // Init parameters to communicate with a database
       qx::QxSqlDatabase::getSingleton()->setDriverName("QSQLITE");
       qx::QxSqlDatabase::getSingleton()->setDatabaseName("./test_qxorm.db");
       qx::QxSqlDatabase::getSingleton()->setHostName("localhost");
       qx::QxSqlDatabase::getSingleton()->setUserName("root");
       qx::QxSqlDatabase::getSingleton()->setPassword("");

       // 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'
       qx::cache::clear();

       // 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 (78 ms) : CREATE TABLE drug (id INTEGER NOT NULL PRIMARY KEY AUTOINCREMENT, name TEXT, desc TEXT)
    [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

    <std.vector-boost.shared_ptr-drug-- class_id="0" tracking_level="0" version="0">
            <count>3</count>
            <item_version>1</item_version>
            <item class_id="1" tracking_level="0" version="1">
                    <px class_id="2" tracking_level="1" version="1" object_id="_0">
                            <id>1</id>
                            <name class_id="3" tracking_level="0" version="0">name1</name>
                            <desc>desc1</desc>
                    </px>
            </item>
            <item>
                    <px class_id_reference="2" object_id="_1">
                            <id>2</id>
                            <name>name2 modified</name>
                            <desc>desc2 modified</desc>
                    </px>
            </item>
            <item>
                    <px class_id_reference="2" object_id="_2">
                            <id>3</id>
                            <name>name3</name>
                            <desc>desc3</desc>
                    </px>
            </item>
    </std.vector-boost.shared_ptr-drug-->