mysql_field_seek

(PHP 4, PHP 5)

mysql_field_seek — 将结果集中的指针设定为制定的字段偏移量

说明

mysql_field_seek ( resource $result , int $field_offset ) : int

用指定的字段偏移量检索。如果下一个 mysql_fetch_field() 的调用不包括字段偏移量，则会返回本次 mysql_field_seek() 中指定的偏移量的字段。

User Contributed Notes

adrien dot gibrat at gmail dot com 04-Oct-2008 01:12


Not dumb at all!!



It means that "mysql_field_seek" and "mysql_data_seek" are moving the same cursor... through the rows and columns of the result resource.



Also means that the cursor goes to a new row when it reach a final field(aka column), by exemple while looping with "mysql_fetch_field".



Calling "mysql_fetch_object", "mysql_fetch_array", "mysql_fetch_assoc"

and "mysql_fetch_row" seems to place the cursor at the end of the line.



So calling "mysql_fetch_field" without a field index, just after that, will return false.

chris at igwsolutions dot com 25-Apr-2008 03:23


I spent a good deal of time trying to get the example to work, but the example does not work. 

To do what the exaple is trying to do, you would need to use mysql_data_seek



assume we have table named testing which contains

id      name

1       Hassan

2       Jack

3       Rose

---------------



Here is an expample that will do the above example. 



Since I am more comfortable in a OOP setting, I used mysql_fetch_object



<?php

    require("myConnenctionFile.php");

    

    $sql="SELECT  * from testing";

    $result=mysql_query($sql);



    $row = mysql_fetch_object($result);

    echo $row->id . ' ' . $row->name; // Output is (1      Hassan)

    mysql_data_seek($result,2);

    $row = mysql_fetch_object($result);

    echo $row->id . ' ' . $row->name; // Output is (3      Rose)

    echo "<BR><BR>";

?>

Hassan Kazem 10-Jan-2008 10:34


an example of this function

assume we have table1 which contains

ID      Name

1       Hassan

2       Jack

3       Rose

---------------

<?php 

mysql_connect("sql.server.com", "username", "password") or die(mysql_error()); 

mysql_select_db("database") or die(mysql_error()); 

$sql="SELECT  * from table1";

$result=mysql_query($sql);

$row = mysql_fetch_array($result);

echo $row['ID'] . ' ' . $row['Name']; // Output is (1      Hassan)

mysql_field_seek($result,2);

echo $row['ID'] . ' ' . $row['Name']; // Output is (3      Rose)

?>

---------------

// You can see that the seek command forwarded the pointer one step and skipped row number 2

poulpillusion at free dot fr 17-Apr-2007 07:44


A dumb comment... but it may save people some time : 

mysql_field_seek != mysql_data_seek



In order to fetch again the results of a resource result from the beginning, you will use mysql_data_seek(id, 0)