public function preExecute(SelectInterface $query = NULL)
{
// If no query object is passed in, use $this.
if (!isset($query)) {
$query = $this;
}
return $this->query->preExecute($query);
}
/**
* Generates a hash from a query object, to be used as part of the cache key.
*
* This smart caching strategy saves Drupal from querying and rendering to
* HTML when the underlying query is unchanged.
*
* Expensive queries should use the query builder to create the query and then
* call this function. Executing the query and formatting results should
* happen in a #pre_render callback.
*
* @param \Drupal\Core\Database\Query\SelectInterface $query
* A select query object.
*
* @return string
* A hash of the query arguments.
*/
public static function keyFromQuery(SelectInterface $query)
{
$query->preExecute();
$keys = array((string) $query, $query->getArguments());
return hash('sha256', serialize($keys));
}
/**
* Creates a temporary table from a select query.
*
* Will return the name of a table containing the item IDs of all results, or
* FALSE on failure.
*
* @param \Drupal\Core\Database\Query\SelectInterface $db_query
* The select query whose results should be stored in the temporary table.
*
* @return string|false
* The name of the temporary table, or FALSE on failure.
*/
protected function getTemporaryResultsTable(SelectInterface $db_query) {
// We only need the id field, not the score.
$fields = &$db_query->getFields();
unset($fields['score']);
if (count($fields) != 1 || !isset($fields['item_id'])) {
$this->getLogger()->warning('Error while adding facets: only "item_id" field should be used, used are: @fields.', array('@fields' => implode(', ', array_keys($fields))));
return FALSE;
}
$expressions = &$db_query->getExpressions();
$expressions = array();
$db_query->distinct();
if (!$db_query->preExecute()) {
return FALSE;
}
$args = $db_query->getArguments();
return $this->database->queryTemporary((string) $db_query, $args);
}
/**
* Creates a temporary table from a select query.
*
* Will return the name of a table containing the item IDs of all results, or
* FALSE on failure.
*
* @param \Drupal\Core\Database\Query\SelectInterface $db_query
* The select query whose results should be stored in the temporary table.
*
* @return string|false
* The name of the temporary table, or FALSE on failure.
*/
protected function getTemporaryResultsTable(SelectInterface $db_query)
{
// We only need the id field, not the score.
$fields =& $db_query->getFields();
unset($fields['score']);
if (count($fields) != 1 || !isset($fields['item_id'])) {
$this->getLogger()->warning('Error while adding facets: only "item_id" field should be used, used are: @fields.', array('@fields' => implode(', ', array_keys($fields))));
return FALSE;
}
$expressions =& $db_query->getExpressions();
$expressions = array();
// If there's a GROUP BY for item_id, we leave that, all others need to be
// discarded.
$group_by =& $db_query->getGroupBy();
$group_by = array_intersect_key($group_by, array('t.item_id' => TRUE));
$db_query->distinct();
if (!$db_query->preExecute()) {
return FALSE;
}
$args = $db_query->getArguments();
try {
$result = $this->database->queryTemporary((string) $db_query, $args);
} catch (\PDOException $e) {
watchdog_exception('search_api', $e, '%type while trying to create a temporary table: @message in %function (line %line of %file).');
return FALSE;
}
return $result;
}
