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50
51#include <QtWidgets>
52#include <QtSql>
53
54#include "../connection.h"
55
56#include <memory>
57
58void initializeModel(QSqlRelationalTableModel *model)
59{
60//! [0]
61 model->setTable("employee");
62//! [0]
63
64 model->setEditStrategy(QSqlTableModel::OnManualSubmit);
65//! [1]
66 model->setRelation(column: 2, relation: QSqlRelation("city", "id", "name"));
67//! [1] //! [2]
68 model->setRelation(column: 3, relation: QSqlRelation("country", "id", "name"));
69//! [2]
70
71//! [3]
72 model->setHeaderData(section: 0, orientation: Qt::Horizontal, value: QObject::tr(s: "ID"));
73 model->setHeaderData(section: 1, orientation: Qt::Horizontal, value: QObject::tr(s: "Name"));
74 model->setHeaderData(section: 2, orientation: Qt::Horizontal, value: QObject::tr(s: "City"));
75 model->setHeaderData(section: 3, orientation: Qt::Horizontal, value: QObject::tr(s: "Country"));
76//! [3]
77
78 model->select();
79}
80
81std::unique_ptr<QTableView> createView(const QString &title, QSqlTableModel *model)
82{
83//! [4]
84 std::unique_ptr<QTableView> view{new QTableView};
85 view->setModel(model);
86 view->setItemDelegate(new QSqlRelationalDelegate(view.get()));
87//! [4]
88 view->setWindowTitle(title);
89 return view;
90}
91
92void createRelationalTables()
93{
94 QSqlQuery query;
95 query.exec(query: "create table employee(id int primary key, name varchar(20), city int, country int)");
96 query.exec(query: "insert into employee values(1, 'Espen', 5000, 47)");
97 query.exec(query: "insert into employee values(2, 'Harald', 80000, 49)");
98 query.exec(query: "insert into employee values(3, 'Sam', 100, 1)");
99
100 query.exec(query: "create table city(id int, name varchar(20))");
101 query.exec(query: "insert into city values(100, 'San Jose')");
102 query.exec(query: "insert into city values(5000, 'Oslo')");
103 query.exec(query: "insert into city values(80000, 'Munich')");
104
105 query.exec(query: "create table country(id int, name varchar(20))");
106 query.exec(query: "insert into country values(1, 'USA')");
107 query.exec(query: "insert into country values(47, 'Norway')");
108 query.exec(query: "insert into country values(49, 'Germany')");
109}
110
111int main(int argc, char *argv[])
112{
113 QApplication app(argc, argv);
114 if (!createConnection())
115 return EXIT_FAILURE;
116
117 createRelationalTables();
118
119 QSqlRelationalTableModel model;
120
121 initializeModel(model: &model);
122
123 std::unique_ptr<QTableView> view = createView(title: QObject::tr(s: "Relational Table Model"), model: &model);
124 view->show();
125
126 return app.exec();
127}
128

source code of qtbase/examples/sql/relationaltablemodel/relationaltablemodel.cpp