PHP: PDOStatement::rowCount

Описание

int PDOStatement::rowCount ( void )

PDOStatement::rowCount() returns the number of rows affected by the last DELETE, INSERT, or UPDATE statement executed by the corresponding PDOStatement object.

If the last SQL statement executed by the associated PDOStatement was a SELECT statement, some databases may return the number of rows returned by that statement. However, this behaviour is not guaranteed for all databases and should not be relied on for portable applications.

Примеры

Пример 1. Return the number of deleted rows
PDOStatement::rowCount() returns the number of rows affected by a DELETE, INSERT, or UPDATE statement.

<?php /* Delete all rows from the FRUIT table */ $del = $dbh->prepare('DELETE FROM fruit'); $del->execute(); /* Return number of rows that were deleted */ print("Return number of rows that were deleted:\n"); $count = $del->rowCount(); print("Deleted $count rows.\n"); ?>
Результат выполнения данного примера:
Deleted 9 rows.

Пример 2. Counting rows returned by a SELECT statement
For most databases, PDOStatement::rowCount() does not return the number of rows affected by a SELECT statement. Instead, use PDO::query() to issue a SELECT COUNT(*) statement with the same predicates as your intended SELECT statement, then use PDOStatement::fetchColumn() to retrieve the number of rows that will be returned. Your application can then perform the correct action.

<?php $sql = "SELECT COUNT(*) FROM fruit WHERE calories > 100"; if ($res = $conn->query($sql)) { /* Check the number of rows that match the SELECT statement */ if ($res->fetchColumn() > 0) { /* Issue the real SELECT statement and work with the results */ $sql = "SELECT name FROM fruit WHERE calories > 100"; foreach ($conn->query($sql) as $row) { print "Name: " . $row['NAME'] . "\n"; } } /* No rows matched -- do something else */ else { print "No rows matched the query."; } } $res = null; $conn = null; ?>
Результат выполнения данного примера:
apple banana orange pear

Смотрите также

PDOStatement::columnCount()

PDOStatement::fetchColumn()

PDOStatement::query()

PDOStatement::rowCount

pcdinh at phpvietnam dot net
21-Mar-2006 02:39


In some case you need to know how many row are retrieved from a select query (i.e to page a result set) you can use:



$totalRows = count($resultSet->fetchAll());



It works on MySQL 5.0.18 and PHP 5.1

Pablo Godel
30-Jan-2006 12:18


For large resultsets the method described below is not very efficient. It is better to do a select COUNT(*).

markjcrane at gmail dot com
29-Nov-2005 04:12


A rowcount that would return the record count with a select statement would be extremely usefull in PDO. However since it doesn't exist here is an another method to return the record count.



$sql = "SELECT * FROM tblusers ";

$prepstatement = $db->prepare($sql);

$prepstatement->execute();



//save the results to array

$result = $prepstatement->fetchAll();



//count the array

$resultcount = count($result);

echo "resultcount : ".$resultcount ."<br>";



foreach($result as $field) {

    echo "username: ".$field[username]."<br>";

    echo "<br>";

}

unset($sql, $result, $resultcount);