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  • mysql_field_seek()

    (PHP 4, PHP 5)

    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。

    参见mysql_fetch_field()。

    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.
    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>";
    ?>
    
    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)
    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