class DatabaseStatementEmpty
Empty implementation of a database statement.
This class satisfies the requirements of being a database statement/result object, but does not actually contain data. It is useful when developers need to safely return an "empty" result set without connecting to an actual database. Calling code can then treat it the same as if it were an actual result set that happens to contain no records.
Hierarchy
- class \DatabaseStatementEmpty implements \Iterator, DatabaseStatementInterface
Expanded class hierarchy of DatabaseStatementEmpty
See also
Related topics
File
- drupal-7.x/
includes/ database/ database.inc, line 2237 - Core systems for the database layer.
View source
class DatabaseStatementEmpty implements Iterator, DatabaseStatementInterface {
public function execute($args = array(), $options = array()) {
return FALSE;
}
public function getQueryString() {
return '';
}
public function rowCount() {
return 0;
}
public function setFetchMode($mode, $a1 = NULL, $a2 = array()) {
return;
}
public function fetch($mode = NULL, $cursor_orientation = NULL, $cursor_offset = NULL) {
return NULL;
}
public function fetchField($index = 0) {
return NULL;
}
public function fetchObject() {
return NULL;
}
public function fetchAssoc() {
return NULL;
}
function fetchAll($mode = NULL, $column_index = NULL, array $constructor_arguments = array()) {
return array();
}
public function fetchCol($index = 0) {
return array();
}
public function fetchAllKeyed($key_index = 0, $value_index = 1) {
return array();
}
public function fetchAllAssoc($key, $fetch = NULL) {
return array();
}
/* Implementations of Iterator. */
public function current() {
return NULL;
}
public function key() {
return NULL;
}
public function rewind() {
// Nothing to do: our DatabaseStatement can't be rewound.
}
public function next() {
// Do nothing, since this is an always-empty implementation.
}
public function valid() {
return FALSE;
}
}
