NULL); // Descending more useful. $options['subquery_order'] = array('default' => 'DESC'); $options['subquery_regenerate'] = array('default' => FALSE, 'bool' => TRUE); $options['subquery_view'] = array('default' => FALSE); $options['subquery_namespace'] = array('default' => FALSE); return $options; } /** * Extends the relationship's basic options, allowing the user to pick * a sort and an order for it. */ function options_form(&$form, &$form_state) { parent::options_form($form, $form_state); // Get the sorts that apply to our base. $sorts = views_fetch_fields($this->definition['base'], 'sort'); foreach ($sorts as $sort_id => $sort) { $sort_options[$sort_id] = "$sort[group]: $sort[title]"; } $base_table_data = views_fetch_data($this->definition['base']); $form['subquery_sort'] = array( '#type' => 'select', '#title' => t('Representative sort criteria'), // Provide the base field as sane default sort option. '#default_value' => !empty($this->options['subquery_sort']) ? $this->options['subquery_sort'] : $this->definition['base'] . '.' . $base_table_data['table']['base']['field'], '#options' => $sort_options, '#description' => theme('advanced_help_topic', array('module' => 'views', 'topic' => 'relationship-representative')) . t("The sort criteria is applied to the data brought in by the relationship to determine how a representative item is obtained for each row. For example, to show the most recent node for each user, pick 'Content: Updated date'."), ); $form['subquery_order'] = array( '#type' => 'radios', '#title' => t('Representative sort order'), '#description' => t("The ordering to use for the sort criteria selected above."), '#options' => array('ASC' => t('Ascending'), 'DESC' => t('Descending')), '#default_value' => $this->options['subquery_order'], ); $form['subquery_namespace'] = array( '#type' => 'textfield', '#title' => t('Subquery namespace'), '#description' => t('Advanced. Enter a namespace for the subquery used by this relationship.'), '#default_value' => $this->options['subquery_namespace'], ); // WIP: This stuff doens't work yet: namespacing issues. // A list of suitable views to pick one as the subview. $views = array('' => ''); $all_views = views_get_all_views(); foreach ($all_views as $view) { // Only get views that are suitable: // - base must the base that our relationship joins towards // - must have fields. if ($view->base_table == $this->definition['base'] && !empty($view->display['default']->display_options['fields'])) { // TODO: check the field is the correct sort? // or let users hang themselves at this stage and check later? if ($view->type == 'Default') { $views[t('Default Views')][$view->name] = $view->name; } else { $views[t('Existing Views')][$view->name] = $view->name; } } } $form['subquery_view'] = array( '#type' => 'select', '#title' => t('Representative view'), '#default_value' => $this->options['subquery_view'], '#options' => $views, '#description' => t('Advanced. Use another view to generate the relationship subquery. This allows you to use filtering and more than one sort. If you pick a view here, the sort options above are ignored. Your view must have the ID of its base as its only field, and should have some kind of sorting.'), ); $form['subquery_regenerate'] = array( '#type' => 'checkbox', '#title' => t('Generate subquery each time view is run.'), '#default_value' => $this->options['subquery_regenerate'], '#description' => t('Will re-generate the subquery for this relationship every time the view is run, instead of only when these options are saved. Use for testing if you are making changes elsewhere. WARNING: seriously impairs performance.'), ); } /** * Helper function to create a pseudo view. * * We use this to obtain our subquery SQL. */ function get_temporary_view() { views_include('view'); $view = new view(); $view->vid = 'new'; // @todo: what's this? $view->base_table = $this->definition['base']; $view->add_display('default'); return $view; } /** * When the form is submitted, take sure to clear the subquery string cache. */ function options_form_submit(&$form, &$form_state) { $cid = 'views_relationship_groupwise_max:' . $this->view->name . ':' . $this->view->current_display . ':' . $this->options['id']; cache_clear_all($cid, 'cache_views_data'); } /** * Generate a subquery given the user options, as set in the options. * These are passed in rather than picked up from the object because we * generate the subquery when the options are saved, rather than when the view * is run. This saves considerable time. * * @param $options * An array of options: * - subquery_sort: the id of a views sort. * - subquery_order: either ASC or DESC. * @return * The subquery SQL string, ready for use in the main query. */ function left_query($options) { // Either load another view, or create one on the fly. if ($options['subquery_view']) { $temp_view = views_get_view($options['subquery_view']); // Remove all fields from default display unset($temp_view->display['default']->display_options['fields']); } else { // Create a new view object on the fly, which we use to generate a query // object and then get the SQL we need for the subquery. $temp_view = $this->get_temporary_view(); // Add the sort from the options to the default display. // This is broken, in that the sort order field also gets added as a // select field. See http://drupal.org/node/844910. // We work around this further down. $sort = $options['subquery_sort']; list($sort_table, $sort_field) = explode('.', $sort); $sort_options = array('order' => $options['subquery_order']); $temp_view->add_item('default', 'sort', $sort_table, $sort_field, $sort_options); } // Get the namespace string. $temp_view->namespace = (!empty($options['subquery_namespace'])) ? '_'. $options['subquery_namespace'] : '_INNER'; $this->subquery_namespace = (!empty($options['subquery_namespace'])) ? '_'. $options['subquery_namespace'] : 'INNER'; // The value we add here does nothing, but doing this adds the right tables // and puts in a WHERE clause with a placeholder we can grab later. $temp_view->args[] = '**CORRELATED**'; // Add the base table ID field. $views_data = views_fetch_data($this->definition['base']); $base_field = $views_data['table']['base']['field']; $temp_view->add_item('default', 'field', $this->definition['base'], $this->definition['field']); // Add the correct argument for our relationship's base // ie the 'how to get back to base' argument. // The relationship definition tells us which one to use. $temp_view->add_item( 'default', 'argument', $this->definition['argument table'], // eg 'term_node', $this->definition['argument field'] // eg 'tid' ); // Build the view. The creates the query object and produces the query // string but does not run any queries. $temp_view->build(); // Now take the SelectQuery object the View has built and massage it // somewhat so we can get the SQL query from it. $subquery = $temp_view->build_info['query']; // Workaround until http://drupal.org/node/844910 is fixed: // Remove all fields from the SELECT except the base id. $fields =& $subquery->getFields(); foreach (array_keys($fields) as $field_name) { // The base id for this subquery is stored in our definition. if ($field_name != $this->definition['field']) { unset($fields[$field_name]); } } // Make every alias in the subquery safe within the outer query by // appending a namespace to it, '_inner' by default. $tables =& $subquery->getTables(); foreach (array_keys($tables) as $table_name) { $tables[$table_name]['alias'] .= $this->subquery_namespace; // Namespace the join on every table. if (isset($tables[$table_name]['condition'])) { $tables[$table_name]['condition'] = $this->condition_namespace($tables[$table_name]['condition']); } } // Namespace fields. foreach (array_keys($fields) as $field_name) { $fields[$field_name]['table'] .= $this->subquery_namespace; $fields[$field_name]['alias'] .= $this->subquery_namespace; } // Namespace conditions. $where =& $subquery->conditions(); $this->alter_subquery_condition($subquery, $where); // Not sure why, but our sort order clause doesn't have a table. // TODO: the call to add_item() above to add the sort handler is probably // wrong -- needs attention from someone who understands it. // In the meantime, this works, but with a leap of faith... $orders =& $subquery->getOrderBy(); foreach ($orders as $order_key => $order) { // But if we're using a whole view, we don't know what we have! if ($options['subquery_view']) { list($sort_table, $sort_field) = explode('.', $order_key); } $orders[$sort_table . $this->subquery_namespace . '.' . $sort_field] = $order; unset($orders[$order_key]); } // The query we get doesn't include the LIMIT, so add it here. $subquery->range(0, 1); // Extract the SQL the temporary view built. $subquery_sql = $subquery->__toString(); // Replace the placeholder with the outer, correlated field. // Eg, change the placeholder ':users_uid' into the outer field 'users.uid'. // We have to work directly with the SQL, because putting a name of a field // into a SelectQuery that it does not recognize (because it's outer) just // makes it treat it as a string. $outer_placeholder = ':' . str_replace('.', '_', $this->definition['outer field']); $subquery_sql = str_replace($outer_placeholder, $this->definition['outer field'], $subquery_sql); return $subquery_sql; } /** * Recursive helper to add a namespace to conditions. * * Similar to _views_query_tag_alter_condition(). * * (Though why is the condition we get in a simple query 3 levels deep???) */ function alter_subquery_condition(QueryAlterableInterface $query, &$conditions) { foreach ($conditions as $condition_id => &$condition) { // Skip the #conjunction element. if (is_numeric($condition_id)) { if (is_string($condition['field'])) { $condition['field'] = $this->condition_namespace($condition['field']); } elseif (is_object($condition['field'])) { $sub_conditions =& $condition['field']->conditions(); $this->alter_subquery_condition($query, $sub_conditions); } } } } /** * Helper function to namespace query pieces. * * Turns 'foo.bar' into 'foo_NAMESPACE.bar'. */ function condition_namespace($string) { return str_replace('.', $this->subquery_namespace . '.', $string); } /** * Called to implement a relationship in a query. * This is mostly a copy of our parent's query() except for this bit with * the join class. */ function query() { // Figure out what base table this relationship brings to the party. $table_data = views_fetch_data($this->definition['base']); $base_field = empty($this->definition['base field']) ? $table_data['table']['base']['field'] : $this->definition['base field']; $this->ensure_my_table(); $def = $this->definition; $def['table'] = $this->definition['base']; $def['field'] = $base_field; $def['left_table'] = $this->table_alias; $def['left_field'] = $this->field; if (!empty($this->options['required'])) { $def['type'] = 'INNER'; } if ($this->options['subquery_regenerate']) { // For testing only, regenerate the subquery each time. $def['left_query'] = $this->left_query($this->options); } else { // Get the stored subquery SQL string. $cid = 'views_relationship_groupwise_max:' . $this->view->name . ':' . $this->view->current_display . ':' . $this->options['id']; $cache = cache_get($cid, 'cache_views_data'); if (isset($cache->data)) { $def['left_query'] = $cache->data; } else { $def['left_query'] = $this->left_query($this->options); cache_set($cid, $def['left_query'], 'cache_views_data'); } } if (!empty($def['join_handler']) && class_exists($def['join_handler'])) { $join = new $def['join_handler']; } else { $join = new views_join_subquery(); } $join->definition = $def; $join->construct(); $join->adjusted = TRUE; // use a short alias for this: $alias = $def['table'] . '_' . $this->table; $this->alias = $this->query->add_relationship($alias, $join, $this->definition['base'], $this->relationship); } }