QxOrm  1.2.3
C++ Object Relational Mapping library
QxSqlRelation_ManyToMany.h
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00003 ** http://www.qxorm.com/
00004 ** http://sourceforge.net/projects/qxorm/
00005 ** Original file by Lionel Marty
00006 **
00007 ** This file is part of the QxOrm library
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00025 
00026 #ifndef _QX_SQL_RELATION_MANY_TO_MANY_H_
00027 #define _QX_SQL_RELATION_MANY_TO_MANY_H_
00028 
00029 #ifdef _MSC_VER
00030 #pragma once
00031 #endif
00032 
00040 #include <QxDao/QxSqlRelation.h>
00041 
00042 namespace qx {
00043 
00048 template <class DataType, class Owner>
00049 class QxSqlRelation_ManyToMany : public QxSqlRelation<DataType, Owner>
00050 {
00051 
00052 private:
00053 
00054    typedef typename QxSqlRelation<DataType, Owner>::type_owner type_owner;
00055    typedef typename QxSqlRelation<DataType, Owner>::type_data type_data;
00056    typedef typename QxSqlRelation<DataType, Owner>::type_container type_container;
00057    typedef typename QxSqlRelation<DataType, Owner>::type_generic_container type_generic_container;
00058    typedef typename QxSqlRelation<DataType, Owner>::type_item type_item;
00059    typedef typename type_generic_container::type_iterator type_iterator;
00060 
00061    enum { is_data_container = QxSqlRelation<DataType, Owner>::is_data_container };
00062 
00063 protected:
00064 
00065    QString m_sExtraTable;           
00066    QString m_sForeignKeyOwner;      
00067    QString m_sForeignKeyDataType;   
00068 
00069 public:
00070 
00071    QxSqlRelation_ManyToMany(IxDataMember * p, const QString & sExtraTable, const QString & sForeignKeyOwner, const QString & sForeignKeyDataType) : QxSqlRelation<DataType, Owner>(p), m_sExtraTable(sExtraTable), m_sForeignKeyOwner(sForeignKeyOwner), m_sForeignKeyDataType(sForeignKeyDataType) { this->verifyParameters(); }
00072    virtual ~QxSqlRelation_ManyToMany() { BOOST_STATIC_ASSERT(is_data_container); }
00073 
00074    virtual QString getDescription() const                                     { return "relation many-to-many"; }
00075    virtual QString getExtraTable() const                                      { return m_sExtraTable; }
00076    virtual bool getCartesianProduct() const                                   { return true; }
00077    virtual void createTable(QxSqlRelationParams & params) const               { Q_UNUSED(params); }
00078    virtual void lazySelect(QxSqlRelationParams & params) const                { Q_UNUSED(params); }
00079    virtual void lazyFrom(QxSqlRelationParams & params) const                  { Q_UNUSED(params); }
00080    virtual void eagerFrom(QxSqlRelationParams & params) const                 { Q_UNUSED(params); }
00081    virtual void lazyJoin(QxSqlRelationParams & params) const                  { Q_UNUSED(params); }
00082    virtual void lazyWhere(QxSqlRelationParams & params) const                 { Q_UNUSED(params); }
00083    virtual void eagerWhere(QxSqlRelationParams & params) const                { Q_UNUSED(params); }
00084    virtual void lazyWhereSoftDelete(QxSqlRelationParams & params) const       { Q_UNUSED(params); }
00085    virtual void lazyFetch_ResolveInput(QxSqlRelationParams & params) const    { Q_UNUSED(params); }
00086    virtual void eagerFetch_ResolveInput(QxSqlRelationParams & params) const   { Q_UNUSED(params); }
00087    virtual void lazyFetch_ResolveOutput(QxSqlRelationParams & params) const   { Q_UNUSED(params); }
00088    virtual void lazyInsert(QxSqlRelationParams & params) const                { Q_UNUSED(params); }
00089    virtual void lazyInsert_Values(QxSqlRelationParams & params) const         { Q_UNUSED(params); }
00090    virtual void lazyUpdate(QxSqlRelationParams & params) const                { Q_UNUSED(params); }
00091    virtual void lazyInsert_ResolveInput(QxSqlRelationParams & params) const   { Q_UNUSED(params); }
00092    virtual void lazyUpdate_ResolveInput(QxSqlRelationParams & params) const   { Q_UNUSED(params); }
00093    virtual QSqlError onBeforeSave(QxSqlRelationParams & params) const         { Q_UNUSED(params); return QSqlError(); }
00094 
00095    virtual QVariant getIdFromQuery(bool bEager, QxSqlRelationParams & params) const
00096    {
00097       QString sId; IxDataMember * pId = this->getDataId(); if (! bEager || ! pId) { return QVariant(); }
00098       for (int i = 0; i < pId->getNameCount(); i++) { sId += params.query().value(params.offset() + i).toString() + "|"; }
00099       return QVariant(sId);
00100    }
00101 
00102    virtual void updateOffset(bool bEager, QxSqlRelationParams & params) const
00103    {
00104       if (! bEager) { return; }
00105       long lOffsetNew = params.offset() + this->getDataCount();
00106       lOffsetNew += (this->getDataId() ? this->getDataId()->getNameCount() : 0);
00107       lOffsetNew += (this->m_oSoftDelete.isEmpty() ? 0 : 1);
00108       params.setOffset(lOffsetNew);
00109    }
00110 
00111    virtual void eagerSelect(QxSqlRelationParams & params) const
00112    {
00113       long l1(0);
00114       QString & sql = params.sql();
00115       IxDataMember * p = NULL; IxDataMember * pId = this->getDataId(); qAssert(pId);
00116       QString tableAlias = this->tableAlias(params);
00117       if (pId) { sql += (pId->getSqlTablePointNameAsAlias(tableAlias) + ", "); }
00118       while ((p = this->nextData(l1))) { sql += (p->getSqlTablePointNameAsAlias(tableAlias) + ", "); }
00119       if (! this->m_oSoftDelete.isEmpty()) { sql += (this->m_oSoftDelete.buildSqlTablePointName(tableAlias) + ", "); }
00120    }
00121 
00122    virtual void eagerJoin(QxSqlRelationParams & params) const
00123    {
00124       QString & sql = params.sql();
00125       IxDataMember * pIdOwner = params.builder().getDataId(); qAssert(pIdOwner);
00126       IxDataMember * pIdData = this->getDataId(); qAssert(pIdData);
00127       QString table = this->table(); QString tableAlias = this->tableAlias(params); QString tableOwner = params.builder().table();
00128       if (! pIdOwner || ! pIdData) { return; }
00129       QStringList lstForeignKeyOwner = m_sForeignKeyOwner.split("|");
00130       QStringList lstForeignKeyDataType = m_sForeignKeyDataType.split("|");
00131       qAssert(pIdOwner->getNameCount() == lstForeignKeyOwner.count());
00132       qAssert(pIdData->getNameCount() == lstForeignKeyDataType.count());
00133       sql += this->getSqlJoin() + m_sExtraTable + " ON ";
00134       for (int i = 0; i < pIdOwner->getNameCount(); i++)
00135       { sql += pIdOwner->getSqlAlias(tableOwner, true, i) + " = " + m_sExtraTable + "." + lstForeignKeyOwner.at(i) + " AND "; }
00136       sql = sql.left(sql.count() - 5); // Remove last " AND "
00137       sql += this->getSqlJoin() + table + " " + tableAlias + " ON ";
00138       params.builder().addSqlQueryAlias(table, tableAlias);
00139       for (int i = 0; i < pIdData->getNameCount(); i++)
00140       { sql += m_sExtraTable + "." + lstForeignKeyDataType.at(i) + " = " + pIdData->getSqlAlias(tableAlias, true, i) + " AND "; }
00141       sql = sql.left(sql.count() - 5); // Remove last " AND "
00142    }
00143 
00144    virtual void eagerWhereSoftDelete(QxSqlRelationParams & params) const
00145    {
00146       if (this->m_oSoftDelete.isEmpty()) { return; }
00147       QString & sql = params.sql();
00148       QString tableAlias = this->tableAlias(params);
00149       sql += qx::IxSqlQueryBuilder::addSqlCondition(sql);
00150       sql += this->m_oSoftDelete.buildSqlQueryToFetch(tableAlias);
00151    }
00152 
00153    virtual void eagerFetch_ResolveOutput(QxSqlRelationParams & params) const
00154    {
00155       if (! this->verifyOffset(params, true)) { return; }
00156       QSqlQuery & query = params.query();
00157       IxDataMember * p = NULL; IxDataMember * pId = this->getDataId(); qAssert(pId);
00158       long lIndex = 0; long lOffsetId = (pId ? pId->getNameCount() : 0); bool bValidId(false);
00159       long lOffsetOld = params.offset(); this->updateOffset(true, params);
00160       for (int i = 0; i < pId->getNameCount(); i++)
00161       { QVariant v = query.value(lOffsetOld + i); bValidId = (bValidId || qx::trait::is_valid_primary_key(v)); }
00162       if (! bValidId) { return; }
00163       type_item item = this->createItem();
00164       type_data & item_val = item.value_qx();
00165       for (int i = 0; i < pId->getNameCount(); i++)
00166       { QVariant v = query.value(lOffsetOld + i); qx::cvt::from_variant(v, item.key(), "", i); }
00167       for (int i = 0; i < pId->getNameCount(); i++)
00168       { QVariant v = query.value(lOffsetOld + i); pId->fromVariant((& item_val), v, "", i); }
00169       while ((p = this->nextData(lIndex)))
00170       { p->fromVariant((& item_val), query.value(lIndex + lOffsetOld + lOffsetId - 1)); }
00171       type_generic_container::insertItem(this->getContainer(params), item);
00172    }
00173 
00174    virtual QSqlError onAfterSave(QxSqlRelationParams & params) const
00175    {
00176       QSqlError daoError = qx::dao::save(this->getContainer(params), (& params.database()));
00177       if (daoError.isValid()) { return daoError; }
00178       daoError = this->deleteFromExtraTable(params);
00179       if (daoError.isValid()) { return daoError; }
00180       daoError = this->insertIntoExtraTable(params);
00181       if (daoError.isValid()) { return daoError; }
00182       return QSqlError();
00183    }
00184 
00185    virtual QString createExtraTable() const
00186    {
00187       IxDataMember * pIdOwner = this->getDataIdOwner(); qAssert(pIdOwner);
00188       IxDataMember * pIdData = this->getDataId(); qAssert(pIdData);
00189       if (! pIdOwner || ! pIdData) { return ""; }
00190 
00191       bool bOldPKOwner = pIdOwner->getIsPrimaryKey(); pIdOwner->setIsPrimaryKey(false);
00192       bool bOldPKData = ((pIdOwner == pIdData) ? bOldPKOwner : pIdData->getIsPrimaryKey()); pIdData->setIsPrimaryKey(false);
00193       bool bOldAIOwner = pIdOwner->getAutoIncrement(); pIdOwner->setAutoIncrement(false);
00194       bool bOldAIData = ((pIdOwner == pIdData) ? bOldAIOwner : pIdData->getAutoIncrement()); pIdData->setAutoIncrement(false);
00195 
00196       QString sql = "CREATE TABLE IF NOT EXISTS " + m_sExtraTable + " (";
00197       sql += pIdOwner->getSqlNameAndTypeAndParams(", ", m_sForeignKeyOwner) + ", "; qAssert(! pIdOwner->getSqlType().isEmpty());
00198       sql += pIdData->getSqlNameAndTypeAndParams(", ", m_sForeignKeyDataType) + ", "; qAssert(! pIdData->getSqlType().isEmpty());
00199       sql = sql.left(sql.count() - 2); // Remove last ", "
00200       sql += ")";
00201 
00202       pIdOwner->setIsPrimaryKey(bOldPKOwner); pIdData->setIsPrimaryKey(bOldPKData);
00203       pIdOwner->setAutoIncrement(bOldAIOwner); pIdData->setAutoIncrement(bOldAIData);
00204       qDebug("[QxOrm] create extra-table (relation many-to-many) : %s", qPrintable(sql));
00205       return sql;
00206    }
00207 
00208 private:
00209 
00210    inline void verifyParameters()
00211    { qAssert(! m_sExtraTable.isEmpty() && ! m_sForeignKeyOwner.isEmpty() && ! m_sForeignKeyDataType.isEmpty() && (m_sForeignKeyOwner != m_sForeignKeyDataType)); }
00212 
00213    QSqlError deleteFromExtraTable(QxSqlRelationParams & params) const
00214    {
00215       IxDataMember * pIdOwner = params.builder().getDataId(); qAssert(pIdOwner);
00216       QString sql = "DELETE FROM " + m_sExtraTable + " WHERE ";
00217       QStringList lstForeignKeyOwner = m_sForeignKeyOwner.split("|");
00218       qAssert(pIdOwner->getNameCount() == lstForeignKeyOwner.count());
00219       for (int i = 0; i < pIdOwner->getNameCount(); i++)
00220       { sql += m_sExtraTable + "." + lstForeignKeyOwner.at(i) + " = " + pIdOwner->getSqlPlaceHolder("", i) + " AND "; }
00221       sql = sql.left(sql.count() - 5); // Remove last " AND "
00222       qDebug("[QxOrm] sql query (extra-table) : %s", qPrintable(sql));
00223 
00224       QSqlQuery queryDelete(params.database());
00225       queryDelete.prepare(sql);
00226       pIdOwner->setSqlPlaceHolder(queryDelete, params.owner());
00227       if (! queryDelete.exec()) { return queryDelete.lastError(); }
00228       return QSqlError();
00229    }
00230 
00231    QSqlError insertIntoExtraTable(QxSqlRelationParams & params) const
00232    {
00233       IxDataMember * pIdOwner = params.builder().getDataId(); qAssert(pIdOwner);
00234       IxDataMember * pIdData = this->getDataId(); qAssert(pIdData);
00235       if (! pIdOwner || ! pIdData) { return QSqlError(); }
00236       QStringList lstForeignKeyOwner = m_sForeignKeyOwner.split("|");
00237       QStringList lstForeignKeyDataType = m_sForeignKeyDataType.split("|");
00238       qAssert(pIdOwner->getNameCount() == lstForeignKeyOwner.count());
00239       qAssert(pIdData->getNameCount() == lstForeignKeyDataType.count());
00240 
00241       QString sql = "INSERT INTO " + m_sExtraTable + " (";
00242       sql += pIdOwner->getSqlName(", ", m_sForeignKeyOwner) + ", " + pIdData->getSqlName(", ", m_sForeignKeyDataType);
00243       sql += ") VALUES (";
00244       sql += pIdOwner->getSqlPlaceHolder("", -1, ", ", m_sForeignKeyOwner) + ", " + pIdData->getSqlPlaceHolder("", -1, ", ", m_sForeignKeyDataType) + ")";
00245       qDebug("[QxOrm] sql query (extra-table) : %s", qPrintable(sql));
00246 
00247       type_item item;
00248       type_container container = this->getContainer(params);
00249       type_iterator itr = type_generic_container::begin(container, item);
00250       type_iterator itr_end = type_generic_container::end(container);
00251       QSqlQuery queryInsert(params.database());
00252       queryInsert.prepare(sql);
00253 
00254       while (itr != itr_end)
00255       {
00256          pIdOwner->setSqlPlaceHolder(queryInsert, params.owner(), "", m_sForeignKeyOwner);
00257          pIdData->setSqlPlaceHolder(queryInsert, (& item.value_qx()), "", m_sForeignKeyDataType);
00258          if (! queryInsert.exec()) { return queryInsert.lastError(); }
00259          itr = type_generic_container::next(container, itr, item);
00260       }
00261 
00262       return QSqlError();
00263    }
00264 
00265 };
00266 
00267 } // namespace qx
00268 
00269 #endif // _QX_SQL_RELATION_MANY_TO_MANY_H_