mysql_data_seek
(PHP 3, PHP 4 , PHP 5)
mysql_data_seek -- Move internal result pointer
Description
bool
mysql_data_seek ( resource result_identifier, int row_number)
Returns TRUE on success or FALSE on failure.
mysql_data_seek() moves the internal row
pointer of the MySQL result associated with the specified result
identifier to point to the specified row number. The next call
to mysql_fetch_row() would return that row.
Row_number starts at 0. The
row_number should be a value in the range from 0 to
mysql_num_rows - 1. However if the result set is empty (mysql_num_rows ==
0), a seek to 0 will fail with a E_WARNING
and mysql_data_seek() will return FALSE.
Example 1. mysql_data_seek() example
<?php
$link = mysql_connect('localhost', 'mysql_user', 'mysql_password');
if (!$link) {
die('Could not connect: ' . mysql_error());
}
$db_selected = mysql_select_db('sample_db');
if (!$db_selected) {
die('Could not select database: ' . mysql_error());
}
$query = 'SELECT last_name, first_name FROM friends';
$result = mysql_query($query);
if (!$result) {
die('Query failed: ' . mysql_error());
}
/* fetch rows in reverse order */
for ($i = mysql_num_rows($result) - 1; $i >= 0; $i--) {
if (!mysql_data_seek($result, $i)) {
echo "Cannot seek to row $i: " . mysql_error() . "\n";
continue;
}
if (!($row = mysql_fetch_assoc($result))) {
continue;
}
echo $row['last_name'] . ' ' . $row['first_name'] . "<br />\n";
}
mysql_free_result($result);
?>
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See also
mysql_query() and
mysql_num_rows().