Esercizi Modifica MongoDB C++

Codegrind Team•Jul 12 2024

Ecco degli esercizi semplici con soluzione per praticare la modifica di dati in MongoDB utilizzando C++ sia in modo sequenziale che OOP.

Esercizio 1: Modifica di un singolo documento usando mongocxx (metodo sequenziale)

Stabilire una connessione a MongoDB e modificare un singolo documento.

#include <mongocxx/client.hpp>
#include <mongocxx/instance.hpp>
#include <mongocxx/uri.hpp>
#include <bsoncxx/json.hpp>
#include <bsoncxx/builder/basic/document.hpp>
#include <iostream>

int main() {
    mongocxx::instance instance{};
    mongocxx::client client{mongocxx::uri{"mongodb://localhost:27017"}};
    auto collection = client["test_db"]["test_collection"];

    bsoncxx::builder::basic::document filter{};
    filter.append(bsoncxx::builder::basic::kvp("name", "John Doe"));

    bsoncxx::builder::basic::document update{};
    update.append(bsoncxx::builder::basic::kvp("$set", bsoncxx::builder::basic::make_document(
        bsoncxx::builder::basic::kvp("age", 35)
    )));

    auto result = collection.update_one(filter.view(), update.view());
    if (result) {
        std::cout << "Documenti modificati: " << result->modified_count() << std::endl;
    } else {
        std::cout << "Nessun documento modificato" << std::endl;
    }

    return 0;
}

Esercizio 2: Modifica di più documenti usando mongocxx (metodo sequenziale)

Stabilire una connessione a MongoDB e modificare più documenti.

#include <mongocxx/client.hpp>
#include <mongocxx/instance.hpp>
#include <mongocxx/uri.hpp>
#include <bsoncxx/json.hpp>
#include <bsoncxx/builder/basic/document.hpp>
#include <iostream>

int main() {
    mongocxx::instance instance{};
    mongocxx::client client{mongocxx::uri{"mongodb://localhost:27017"}};
    auto collection = client["test_db"]["test_collection"];

    bsoncxx::builder::basic::document filter{};
    filter.append(bsoncxx::builder::basic::kvp("status", "active"));

    bsoncxx::builder::basic::document update{};
    update.append(bsoncxx::builder::basic::kvp("$set", bsoncxx::builder::basic::make_document(
        bsoncxx::builder::basic::kvp("status", "inactive")
    )));

    auto result = collection.update_many(filter.view(), update.view());
    if (result) {
        std::cout << "Documenti modificati: " << result->modified_count() << std::endl;
    } else {
        std::cout << "Nessun documento modificato" << std::endl;
    }

    return 0;
}

Esercizio 3: Modifica di un singolo documento usando mongocxx (OOP)

Creare una classe per gestire la connessione a MongoDB e modificare un singolo documento.

#include <mongocxx/client.hpp>
#include <mongocxx/instance.hpp>
#include <mongocxx/uri.hpp>
#include <bsoncxx/json.hpp>
#include <bsoncxx/builder/basic/document.hpp>
#include <iostream>

class MongoDBClient {
private:
    mongocxx::instance instance{};
    mongocxx::client client{mongocxx::uri{"mongodb://localhost:27017"}};
public:
    MongoDBClient() = default;

    void modificaDocumento(const std::string& db_name, const std::string& coll_name, const bsoncxx::document::view& filter, const bsoncxx::document::view& update) {
        auto collection = client[db_name][coll_name];
        auto result = collection.update_one(filter, update);
        if (result) {
            std::cout << "Documenti modificati: " << result->modified_count() << std::endl;
        } else {
            std::cout << "Nessun documento modificato" << std::endl;
        }
    }
};

int main() {
    MongoDBClient client;
    bsoncxx::builder::basic::document filter{};
    filter.append(bsoncxx::builder::basic::kvp("name", "John Doe"));

    bsoncxx::builder::basic::document update{};
    update.append(bsoncxx::builder::basic::kvp("$set", bsoncxx::builder::basic::make_document(
        bsoncxx::builder::basic::kvp("age", 35)
    )));

    client.modificaDocumento("test_db", "test_collection", filter.view(), update.view());
    return 0;
}

Esercizio 4: Modifica di più documenti usando mongocxx (OOP)

Creare una classe per gestire la connessione a MongoDB e modificare più documenti.

#include <mongocxx/client.hpp>
#include <mongocxx/instance.hpp>
#include <mongocxx/uri.hpp>
#include <bsoncxx/json.hpp>
#include <bsoncxx/builder/basic/document.hpp>
#include <iostream>

class MongoDBClient {
private:
    mongocxx::instance instance{};
    mongocxx::client client{mongocxx::uri{"mongodb://localhost:27017"}};
public:
    MongoDBClient() = default;

    void modificaDocumenti(const std::string& db_name, const std::string& coll_name, const bsoncxx::document::view& filter, const bsoncxx::document::view& update) {
        auto collection = client[db_name][coll_name];
        auto result = collection.update_many(filter, update);
        if (result) {
            std::cout << "Documenti modificati: " << result->modified_count() << std::endl;
        } else {
            std::cout << "Nessun documento modificato" << std::endl;
        }
    }
};

int main() {
    MongoDBClient client;
    bsoncxx::builder::basic::document filter{};
    filter.append(bsoncxx::builder::basic::kvp("status", "active"));

    bsoncxx::builder::basic::document update{};
    update.append(bsoncxx::builder::basic::kvp("$set", bsoncxx::builder::basic::make_document(
        bsoncxx::builder::basic::kvp("status", "inactive")
    )));

    client.modificaDocumenti("test_db", "test_collection", filter.view(), update.view());
    return 0;
}

Esercizio 5: Modifica di un singolo documento usando mongo-c-driver (metodo sequenziale)

Stabilire una connessione a MongoDB e modificare un singolo documento usando mongo-c-driver.

#include <mongoc/mongoc.h>
#include <bson/bson.h>
#include <iostream>

int main() {
    mongoc_init();

    mongoc_client_t *client = mongoc_client_new("mongodb://localhost:27017");
    mongoc_collection_t *collection = mongoc_client_get_collection(client, "test_db", "test_collection");

    bson_t *filter = BCON_NEW("name", BCON_UTF8("John Doe"));
    bson_t *update = BCON_NEW("$set", "{", "age", BCON_INT32(35), "}");

    bson_error_t error;
    if (!mongoc_collection_update_one(collection, filter, update, nullptr, nullptr, &error)) {
        std::cerr << "Errore nella modifica del documento: " << error.message << std::endl;
    } else {
        std::cout << "Documento modificato con successo" << std::endl;
    }

    bson_destroy(filter);
    bson_destroy(update);
    mongoc_collection_destroy(collection);
    mongoc_client_destroy(client);
    mongoc_cleanup();

    return 0;
}

Esercizio 6: Modifica di più documenti usando mongo-c-driver (OOP)

Creare una classe per gestire la connessione a MongoDB e

modificare più documenti usando mongo-c-driver.

#include <mongoc/mongoc.h>
#include <bson/bson.h>
#include <iostream>

class MongoDBClient {
private:
    mongoc_client_t *client;
public:
    MongoDBClient(const std::string& uri) {
        mongoc_init();
        client = mongoc_client_new(uri.c_str());
    }

    ~MongoDBClient() {
        mongoc_client_destroy(client);
        mongoc_cleanup();
    }

    void modificaDocumenti(const std::string& db_name, const std::string& coll_name, const bson_t* filter, const bson_t* update) {
        mongoc_collection_t *collection = mongoc_client_get_collection(client, db_name.c_str(), coll_name.c_str());
        bson_error_t error;
        if (!mongoc_collection_update_many(collection, filter, update, nullptr, nullptr, &error)) {
            std::cerr << "Errore nella modifica dei documenti: " << error.message << std::endl;
        } else {
            std::cout << "Documenti modificati con successo" << std::endl;
        }
        mongoc_collection_destroy(collection);
    }
};

int main() {
    MongoDBClient client("mongodb://localhost:27017");

    bson_t *filter = BCON_NEW("status", BCON_UTF8("active"));
    bson_t *update = BCON_NEW("$set", "{", "status", BCON_UTF8("inactive"), "}");

    client.modificaDocumenti("test_db", "test_collection", filter, update);

    bson_destroy(filter);
    bson_destroy(update);

    return 0;
}