PHP Manual: Returns the number of rows affected by the last SQL statement

Description

public int PDOStatement::rowCount()

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

For statements that produce result sets, such as SELECT, the behavior is undefined and can be different for each driver. Some databases may return the number of rows produced by that statement (e.g. MySQL in buffered mode), but this behaviour is not guaranteed for all databases and should not be relied on for portable applications.

Note:
This method returns "0" (zero) with the SQLite driver at all times, and with the PostgreSQL driver only when setting the PDO::ATTR_CURSOR statement attribute to PDO::CURSOR_SCROLL.

Parameters

This function has no parameters.

Return Values

Returns the number of rows.

Errors/Exceptions

Emits an error with level E_WARNING if the attribute PDO::ATTR_ERRMODE is set to PDO::ERRMODE_WARNING.

Throws a PDOException if the attribute PDO::ATTR_ERRMODE is set to PDO::ERRMODE_EXCEPTION.

Examples

Example #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";
?>

The above example will output something similar to:

Return number of rows that were deleted:
Deleted 9 rows.

Example #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 matching rows.

<?php
$sql = "SELECT COUNT(*) FROM fruit WHERE calories > 100";
$res = $conn->query($sql);
$count = $res->fetchColumn();

print "There are " .  $count . " matching records.";