MySQL數(shù)據(jù)庫函數(shù)詳解(6)

字號： 小 中 大

(11) object mysql_fetch_field(int result [,int col_num]);
    返回結果集中給定列的相關元數(shù)據(jù)信息，如果沒有這樣的列，則返回假。如果省略col_num，則對mysql_fetch_field()的后繼調(diào)用返回結果集后續(xù)列的信息。如果不再有剩余的列。則返回值為假。如果指定了col_num，則其取值范圍為0到mysql_num_fields()-1。在此情況下，mysql_num_fields()返回給定列的相關信息，如果col_num超出范圍，返回假。
        $link=mysql_pconnect("localhost","sunsoft","suixiang") or die("Could not connect");
    mysql_select_db("stamp_db") or die("Could not select database");
    $query="SELECT * FROM president";
    $result=mysql_query($query) or die("Query failed");
    for($i=0;$i    {
    printf("information for column %d:
    ",$i);
    $meta=mysql_fetch_field($result);
    if(!$meta)
    {
    print("No information available
    ");
    continue;
    }
    print("

    ");
    printf("blob: %s
    ",$meta->blob);
    printf("max_length: %s
    ",$meta->max_length);
    printf("multiple_key: %s
    ",$meta->multiple_key);
    printf("name: %s
    ",$meta->name);
    printf("not_null: %s
    ",$meta->not_null);
    printf("numeric: %s
    ",$meta->numeric);
    printf("primary_key: %s
    ",$meta->primary_key);
    printf("table: %s
    ",$meta->table);
    printf("type: %s
    ",$meta->type);
    printf("unique_key: %s
    ",$meta->unique_key);
    printf("unsigned: %s
    ",$meta->unsigned);
    printf("zerofill: %s
    ",$meta->zerofill);
    print("

    ");
    }
    ?>
    (12) array mysql_fetch_lengths(int result);
    本函式將 mysql_fetch_row() 處理過的最后一列資料的各欄位資料長度放在陣列變數(shù)之中。若執(zhí)行失敗則傳回 false 值。傳回陣列的第一筆資料索引值是 0。
        $link=mysql_pconnect("localhost","sunsoft","suixiang") or die("Could not connect");
    mysql_select_db("stamp_db") or die("Could not select database");
    $query="SELECT * FROM president" or die("Query failed");
    $row_num=0;
    while(mysql_fetch_row($result))
    {
    ++$row_num;
    printf("Lengths of values in row %d:
    ",$row_num);
    $len=mysql_fetch_lengths($result);
    if(!$len)
    {
    print("No information available
    ");
    break;
    }
    print("

    ");
    for($i=0;$i    printf("Column %d: %s
    ",$i,$len[$i]);
    print("

    ");
    }
    ?>