C++ TableRef::add_empty_row方法代码示例

SyncFileActionMetadata::SyncFileActionMetadata(const SyncMetadataManager& manager,
                                               Action action,
                                               const std::string& original_name,
                                               const std::string& url,
                                               const std::string& user_identity,
                                               util::Optional<std::string> new_name)
: m_schema(manager.m_file_action_schema)
{
    size_t raw_action = static_cast<size_t>(action);

    // Open the Realm.
    m_realm = Realm::get_shared_realm(manager.get_configuration());

    // Retrieve or create the row for this object.
    TableRef table = ObjectStore::table_for_object_type(m_realm->read_group(), c_sync_fileActionMetadata);
    m_realm->begin_transaction();
    size_t row_idx = table->find_first_string(m_schema.idx_original_name, original_name);
    if (row_idx == not_found) {
        row_idx = table->add_empty_row();
        table->set_string(m_schema.idx_original_name, row_idx, original_name);
    }
    table->set_string(m_schema.idx_new_name, row_idx, new_name);
    table->set_int(m_schema.idx_action, row_idx, raw_action);
    table->set_string(m_schema.idx_url, row_idx, url);
    table->set_string(m_schema.idx_user_identity, row_idx, user_identity);
    m_realm->commit_transaction();
    m_row = table->get(row_idx);
}

void ObjectStore::set_primary_key_for_object(Group& group, StringData object_type, StringData primary_key) {
    TableRef table = group.get_table(c_primaryKeyTableName);

    size_t row = table->find_first_string(c_primaryKeyObjectClassColumnIndex, object_type);

#if REALM_ENABLE_SYNC
    // sync::create_table* functions should have already updated the pk table.
    if (sync::has_object_ids(group)) {
        if (primary_key.size() == 0)
            REALM_ASSERT(row == not_found);
        else {
             REALM_ASSERT(row != not_found);
             REALM_ASSERT(table->get_string(c_primaryKeyPropertyNameColumnIndex, row) == primary_key);
        }
        return;
    }
#endif // REALM_ENABLE_SYNC

    if (row == not_found && primary_key.size()) {
        row = table->add_empty_row();
        table->set_string_unique(c_primaryKeyObjectClassColumnIndex, row, object_type);
        table->set_string(c_primaryKeyPropertyNameColumnIndex, row, primary_key);
        return;
    }
    // set if changing, or remove if setting to nil
    if (primary_key.size() == 0) {
        if (row != not_found) {
            table->move_last_over(row);
        }
    }
    else {
        table->set_string(c_primaryKeyPropertyNameColumnIndex, row, primary_key);
    }
}

void ObjectStore::create_metadata_tables(Group *group) {
    TableRef table = group->get_or_add_table(c_primaryKeyTableName);
    if (table->get_column_count() == 0) {
        table->add_column(type_String, c_primaryKeyObjectClassColumnName);
        table->add_column(type_String, c_primaryKeyPropertyNameColumnName);
    }

    table = group->get_or_add_table(c_metadataTableName);
    if (table->get_column_count() == 0) {
        table->add_column(type_Int, c_versionColumnName);

        // set initial version
        table->add_empty_row();
        table->set_int(c_versionColumnIndex, c_zeroRowIndex, ObjectStore::NotVersioned);
    }
}

void ObjectStore::set_primary_key_for_object(Group *group, StringData object_type, StringData primary_key) {
    TableRef table = group->get_table(c_primaryKeyTableName);

    // get row or create if new object and populate
    size_t row = table->find_first_string(c_primaryKeyObjectClassColumnIndex, object_type);
    if (row == not_found && primary_key.size()) {
        row = table->add_empty_row();
        table->set_string(c_primaryKeyObjectClassColumnIndex, row, object_type);
    }

    // set if changing, or remove if setting to nil
    if (primary_key.size() == 0) {
        if (row != not_found) {
            table->remove(row);
        }
    }
    else {
        table->set_string(c_primaryKeyPropertyNameColumnIndex, row, primary_key);
    }
}

Object Object::create(ContextType& ctx, std::shared_ptr<Realm> const& realm,
                      ObjectSchema const& object_schema, ValueType value,
                      bool try_update, Row* out_row)
{
    realm->verify_in_write();

    // get or create our accessor
    bool created = false;

    // try to get existing row if updating
    size_t row_index = realm::not_found;
    TableRef table = ObjectStore::table_for_object_type(realm->read_group(), object_schema.name);

    bool skip_primary = true;
    if (auto primary_prop = object_schema.primary_key_property()) {
        // search for existing object based on primary key type
        auto primary_value = ctx.value_for_property(value, primary_prop->name,
                                                    primary_prop - &object_schema.persisted_properties[0]);
        if (!primary_value)
            primary_value = ctx.default_value_for_property(object_schema, primary_prop->name);
        if (!primary_value) {
            if (!is_nullable(primary_prop->type))
                throw MissingPropertyValueException(object_schema.name, primary_prop->name);
            primary_value = ctx.null_value();
        }
        row_index = get_for_primary_key_impl(ctx, *table, *primary_prop, *primary_value);

        if (row_index == realm::not_found) {
            created = true;
            if (primary_prop->type == PropertyType::Int) {
#if REALM_HAVE_SYNC_STABLE_IDS
                row_index = sync::create_object_with_primary_key(realm->read_group(), *table, ctx.template unbox<util::Optional<int64_t>>(*primary_value));
#else
                row_index = table->add_empty_row();
                if (ctx.is_null(*primary_value))
                    table->set_null_unique(primary_prop->table_column, row_index);
                else
                    table->set_unique(primary_prop->table_column, row_index, ctx.template unbox<int64_t>(*primary_value));
#endif // REALM_HAVE_SYNC_STABLE_IDS
            }
            else if (primary_prop->type == PropertyType::String) {
                auto value = ctx.template unbox<StringData>(*primary_value);
#if REALM_HAVE_SYNC_STABLE_IDS
                row_index = sync::create_object_with_primary_key(realm->read_group(), *table, value);
#else
                row_index = table->add_empty_row();
                table->set_unique(primary_prop->table_column, row_index, value);
#endif // REALM_HAVE_SYNC_STABLE_IDS
            }
            else {
                REALM_TERMINATE("Unsupported primary key type.");
            }
        }
        else if (!try_update) {
            if (realm->is_in_migration()) {
                // Creating objects with duplicate primary keys is allowed in migrations
                // as long as there are no duplicates at the end, as adding an entirely
                // new column which is the PK will inherently result in duplicates at first
                row_index = table->add_empty_row();
                created = true;
                skip_primary = false;
            }
            else {
                throw std::logic_error(util::format("Attempting to create an object of type '%1' with an existing primary key value '%2'.",
                                                    object_schema.name, ctx.print(*primary_value)));
            }
        }
    }
    else {
#if REALM_HAVE_SYNC_STABLE_IDS
        row_index = sync::create_object(realm->read_group(), *table);
#else
        row_index = table->add_empty_row();
#endif // REALM_HAVE_SYNC_STABLE_IDS
        created = true;
    }

    // populate
    Object object(realm, object_schema, table->get(row_index));
    if (out_row)
        *out_row = object.row();
    for (size_t i = 0; i < object_schema.persisted_properties.size(); ++i) {
        auto& prop = object_schema.persisted_properties[i];
        if (skip_primary && prop.is_primary)
            continue;

        auto v = ctx.value_for_property(value, prop.name, i);
        if (!created && !v)
            continue;

        bool is_default = false;
        if (!v) {
            v = ctx.default_value_for_property(object_schema, prop.name);
            is_default = true;
        }
        if ((!v || ctx.is_null(*v)) && !is_nullable(prop.type) && !is_array(prop.type)) {
            if (prop.is_primary || !ctx.allow_missing(value))
                throw MissingPropertyValueException(object_schema.name, prop.name);
        }
        if (v)
//.........这里部分代码省略.........

static Object create_object(SharedRealm realm, const ObjectSchema &object_schema) {
    TableRef table = get_table(*realm, object_schema);
    return Object(std::move(realm), object_schema, (*table)[table->add_empty_row()]);
}