MySQL數(shù)據(jù)庫(kù)函數(shù)詳解(3)

(5) int mysql_data_seek(int result_id, int row_num);
    由SELECT查詢返回的每個(gè)結(jié)果集都有一個(gè)行游標(biāo)，指示下一個(gè)提取行的函數(shù)(mysql_fetch_array()、mysql_fetch_object()或者mysql_fetch_row())調(diào)用將返回哪一行。mysql_data_seek()將給定結(jié)果集的指針設(shè)置到給定的行。行號(hào)的范圍為0到mysql_num_rows()-1。如果行號(hào)合法，則mysql_data_seek()返回真，否則返回假。
        $link=mysql_pconnect("localhost","sunsoft","suixiang") or die("Could not connect");
    mysql_select_db("samp_db") or die("Could not select database");
    $query="SELECT last_name,first_name FROM president");
    $result=mysql_query($query) or die("Query failed");
    for($i=mysql_num_rows($result)-1;$i>=0;$i-)
    {
    if(!mysql_data_seek($result,$i);
    {
    printf("Cannot seek to row %dn",$i);
    continue;
    }
    if(!$row=mysql_fetch_object($result)))
    continue;
    printf("%d %s
    n",$row->last_name,$row->first_name);
    }
    mysql_free_result($result);
    ?>