PHP Mysql Tutorials, Function, mysql_data

Topic

What is mysql_data_seek function in PHP?
How does mysql_data_seek() works?

Explanation

The mysql_data_seek() function moves internal result pointer.

Syntax

bool mysql_data_seek ( resource result_identifier, int row_number)

Returns TRUE on success or FALSE on failure.

mysql_data_seek() is used to move the internal pointer of resultset returned by mysql_query() to a specific row.

mysql_data_seek() allows you to randomly access the results of a query by seeking (or moving) the internal record pointer of result set to the specified position.The offset starts from '0', if you specify offset as '5', pointer will be moved to fifth row of the result set.Subsequent calls to mysql_fetch_row() will retrieve rows starting from fifth position.

Example:

<?php

// Attempt to connect to the default database server

$link = mysql_connect("mysql_host", "mysql_user", "mysql_password")
or die ("Could not connect");

$db=mysql_select_db("My_database",$link);

// retrieve the mysql character encoding

$data = mysql_query('SELECT * FROM My_table',$link);

// attempt to seek to a specified position

if (!mysql_data_seek($data, 10))
echo 'Seek to record 10 failed!';
else
print_r(mysql_fetch_row($data));

mysql_close($link) ;
?>

Here internal record pointer of result $data is moved to 10th record using function mysql_data_seek($data, 10). Subsequent calls to mysql_fetch_row() will retrieve rows starting from 10th record.

See also: mysql_query() and mysql_num_rows()

mysql_data_seek() Function in PHP