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// SPDX-FileCopyrightText: 2022 Jonah Brüchert <jbb@kaidan.im
//
// SPDX-License-Identifier: BSD-2-Clause
// Qt
#include "qstringliteral.h"
#include <QCoreApplication>
#include <QTimer>
// QCoro
#include <QCoro/QCoroTask>
#include <QCoro/QCoroFuture>
// FutureSQL
#include <ThreadedDatabase>
// STL
#include <tuple>
// A data structure that represents data from the "test" table
struct HelloWorld {
// Types that the database columns can be converted to. The types must be convertible from QVariant.
using ColumnTypes = std::tuple<int, QString>;
// This function gets a row from the database as a tuple, and puts it into the HelloWorld structs.
// If the ColumnTypes already match the types and order of the attributes in the struct, you don't need to implement it.
//
// Try to comment it out, the example should still compile and work.
static HelloWorld fromSql(ColumnTypes &&tuple) {
auto [id, data] = tuple;
return HelloWorld { id, data };
}
// attributes
int id;
QString data;
};
QCoro::Task<> databaseExample() {
// This object contains the database configuration,
// in this case just the path to the SQLite file, and the database type (SQLite).
DatabaseConfiguration config;
config.setDatabaseName(QStringLiteral("database.sqlite"));
config.setType(DatabaseType::SQLite);
// Here we open the database file, and get a handle to the database.
auto database = ThreadedDatabase::establishConnection(config);
// Execute some queries.
co_await database->execute(QStringLiteral("CREATE TABLE IF NOT EXISTS test (id INTEGER PRIMARY KEY AUTOINCREMENT, data TEXT)"));
// Query parameters are bound by position in the query. The execute function is variadic and you can add as many parameters as you need.
co_await database->execute(QStringLiteral("INSERT INTO test (data) VALUES (?))"), QStringLiteral("Hello World"));
// Retrieve some data from the database.
// The data is directly returned as our HelloWorld struct.
auto results = co_await database->getResults<HelloWorld>(QStringLiteral("SELECT * FROM test"));
// Print out the data in the result list
for (const auto &result : results) {
qDebug() << result.id << result.data;
}
// Quit the event loop as we are done
QCoreApplication::instance()->quit();
}
// Just a minimal main function for QCoro, to start the Qt event loop.
int main(int argc, char *argv[]) {
QCoreApplication app(argc, argv);
QTimer::singleShot(0, databaseExample);
return app.exec();
}
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