mysql_data_seek
(PHP 3, PHP 4 )
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.
Note: The function mysql_data_seek() can be used in conjunction
only with mysql_query(), not with mysql_unbuffered_query().
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);
?>
See also mysql_query() and mysql_num_rows().
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