Method executeToDatabase

src/Interpreters/InterpreterAlterQuery.cpp:225–267

}

BlockIO InterpreterAlterQuery::executeToDatabase(const ASTAlterQuery & alter)
{
    BlockIO res;

    if (!alter.cluster.empty())
        return executeDDLQueryOnCluster(query_ptr, getContext(), getRequiredAccess());

    getContext()->checkAccess(getRequiredAccess());
    DatabasePtr database = DatabaseCatalog::instance().getDatabase(alter.database, getContext());
    AlterCommands alter_commands;

    for (const auto & child : alter.command_list->children)
    {
        auto * command_ast = child->as<ASTAlterCommand>();
        if (auto alter_command = AlterCommand::parse(command_ast, getContext()))
            alter_commands.emplace_back(std::move(*alter_command));
        else
            throw Exception("Wrong parameter type in ALTER DATABASE query", ErrorCodes::LOGICAL_ERROR);
    }

    if (!alter_commands.empty())
    {
        /// Only ALTER SETTING is supported.
        for (const auto & command : alter_commands)
        {
            if (command.type != AlterCommand::MODIFY_DATABASE_SETTING)
                throw Exception(ErrorCodes::NOT_IMPLEMENTED, "Unsupported alter type for database engines");
        }

        for (const auto & command : alter_commands)
        {
            if (!command.ignore)
            {
                if (command.type == AlterCommand::MODIFY_DATABASE_SETTING)
                    database->applySettingsChanges(command.settings_changes, getContext());
                else
                    throw Exception(ErrorCodes::NOT_IMPLEMENTED, "Unsupported alter command");
            }
        }
    }

    return res;
}

AccessRightsElements InterpreterAlterQuery::getRequiredAccess() const
{