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

Expanded class hierarchy of DatabaseStatementEmpty

See also

SearchQuery

Related topics

Database abstraction layer
Allow the use of different database servers using the same code base.

File

includes/database/database.inc, line 2352

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;
    }

}

Members

Title Modifiers Object type Summary Overriden Title
DatabaseStatementEmpty::current public function
DatabaseStatementEmpty::execute public function Executes a prepared statement Overrides DatabaseStatementInterface::execute
DatabaseStatementEmpty::fetch public function
DatabaseStatementEmpty::fetchAll function
DatabaseStatementEmpty::fetchAllAssoc public function Returns the result set as an associative array keyed by the given field. Overrides DatabaseStatementInterface::fetchAllAssoc
DatabaseStatementEmpty::fetchAllKeyed public function Returns the entire result set as a single associative array. Overrides DatabaseStatementInterface::fetchAllKeyed
DatabaseStatementEmpty::fetchAssoc public function Fetches the next row and returns it as an associative array. Overrides DatabaseStatementInterface::fetchAssoc
DatabaseStatementEmpty::fetchCol public function Returns an entire single column of a result set as an indexed array. Overrides DatabaseStatementInterface::fetchCol
DatabaseStatementEmpty::fetchField public function Returns a single field from the next record of a result set. Overrides DatabaseStatementInterface::fetchField
DatabaseStatementEmpty::fetchObject public function
DatabaseStatementEmpty::getQueryString public function Gets the query string of this statement. Overrides DatabaseStatementInterface::getQueryString
DatabaseStatementEmpty::key public function
DatabaseStatementEmpty::next public function
DatabaseStatementEmpty::rewind public function
DatabaseStatementEmpty::rowCount public function Returns the number of rows affected by the last SQL statement. Overrides DatabaseStatementInterface::rowCount
DatabaseStatementEmpty::setFetchMode public function
DatabaseStatementEmpty::valid public function

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