XML generation.
Bit of a security risk allowing parameters to select db and table on live server (unless user is restricted or replace the $_GET with fixed value.)
Outputs xml with standard format for <config> part to generate forms in flash.
<?php
//
// makeXML.php?db=dbname&table=tablename
//
set_time_limit(300);
$host = "localhost";
$user = "root";
$password = "root";
$database = $_GET['db'];
$table = $_GET['table'];
mysql_connect($host,$user,$password);
@mysql_select_db($database) or die( "Unable to select database");
$querytext="SELECT * FROM ".$table;
$result=mysql_query($querytext);
if ($result){
$num=mysql_num_rows($result);
}else{
$num=0;
}
?>
<?php
header('Content-Type: text/xml');
echo "<?xml version='1.0'?>";
if ($num > 0){
?>
<<?php echo $table?>>
<config>
<?php
// Display number of fields
echo "<numFields>".mysql_num_fields($result)."</numFields>";
$i = 0;
$primaryKey = "";
$nameArray = array();
$maxLengthArray = array();
$typeArray = array();
while ($i < mysql_num_fields($result)) {
$meta = mysql_fetch_field($result, $i);
$nameArray[$i] = $meta->name;
$maxLengthArray[$i] = $meta->max_length;
$typeArray[$i] = $meta->type;
if ($meta->primary_key){
$primaryKey = $meta->name;
}
$i++;
}
$i = 0;
echo "<fieldNames>";
while ($i < count($nameArray)) {
echo "<field".$i.">".$nameArray[$i]."</field".$i.">";
$i++;
}
echo "</fieldNames>";
$i = 0;
echo "<fieldMaxLength>";
while ($i < count($maxLengthArray)) {
echo "<field".$i.">".$maxLengthArray[$i]."</field".$i.">";
$i++;
}
echo "</fieldMaxLength>";
$i = 0;
echo "<fieldType>";
while ($i < count($typeArray)) {
echo "<field".$i.">".$typeArray[$i]."</field".$i.">";
$i++;
}
echo "</fieldType>";
?>
<primaryKey><?php echo $primaryKey?></primaryKey>
<numRecords><?php echo $num?></numRecords>
</config>
<?php
$i=0;
while ($i < $num) {
$ID=mysql_result($result,$i,"ID");
$value=mysql_result($result,$i,"value");
$title=mysql_result($result,$i,"title");
$description=mysql_result($result,$i,"description");
?>
<row>
<ID><?php echo $ID?></ID>
<weighting><?php echo $value?></weighting>
<title><?php echo $title?></title>
<description><?php echo $description?></description>
</row>
<?php
$i = $i + 1;
}
?>
</<?php echo $table?>>
<?php
}
?>
mysql_fetch_field
(PHP 4, PHP 5)
mysql_fetch_field — Pobiera z wyniku informacje o kolumnie i zwraca jako obiekt
Opis
mysql_fetch_field
( resource
$wynik
[, int $
ofset_pola
] ) : objectZwraca obiekt zawierający informacje o polu.
mysql_fetch_field() pozwala uzyskać informacje o polach w danym wyniku zapytania. Jeżeli ofset pola nie został podany, zwracane zostanie następne pole nie pobrane jeszcze przez mysql_fetch_field().
Właściwości obiektu:
- name - nazwa kolumny
- table - nazwa tabeli do której należy kolumna
- max_length - maksymalna długość kolumny
-
not_null - 1 jeżeli pole nie może być puste (
NULL) - primary_key - 1 jeżeli kolumna jest kluczem podstawowym
- unique_key - 1 jeżeli kolumna jest kluczem unikatowym
- multiple_key - 1 jeżeli kolumna jest kluczem nieunikatowym
- numeric - 1 jeżeli kolumna jest liczbowa
- blob - 1 jeżeli kolumna jest typu BLOOB
- type - typ kolumny
- unsigned - 1 jeżeli kolumna jest bez znaku (plus lub minus)
- zerofill - 1 jeżeli kolumna jest wypełniona zerami
Przykład #1 mysql_fetch_field()
<?php
mysql_connect('localhost','uzytkownik','haslo');
or die ('Nie można się połączyć');
mysql_select_db('baza');
$result = mysql_query('select * from tabela')
or die('Zapytanie zakończone niepowodzeniem');
/* pobieramy dane kolumny */
$i = 0;
while ($i < mysql_num_fields($result)) {
echo "Informacje o kolumnie $i:<br />\n";
$meta = mysql_fetch_field($result);
if (!$meta) {
echo "Informacje niedostępne<br />\n";
}
echo "<pre>
blob: $meta->blob
max_length: $meta->max_length
multiple_key: $meta->multiple_key
name: $meta->name
not_null: $meta->not_null
numeric: $meta->numeric
primary_key: $meta->primary_key
table: $meta->table
type: $meta->type
unique_key: $meta->unique_key
unsigned: $meta->unsigned
zerofill: $meta->zerofill
</pre>";
$i++;
}
mysql_free_result($result);
?>
Patrz także: mysql_field_seek().
add a note
User Contributed Notes 13 notes
TALU ¶
11 years ago
Jonathan ¶
9 years ago
It should be noted that the primary_key member variable is only set to 1 if the primary key on the table is only on that 1 field. If you have a table that has a multiple column primary key, then you will not get what you might expect.
For example:
CREATE TABLE `line_item_table` (
`liForeignKey1` int(11) unsigned not null,
`liForeignKey2` int(11) unsigned not null,
PRIMARY KEY (`liForeignKey1`, `liForeignKey2`)
) ENGINE=MyISAM;
While you might expect that primary_key == 1 for both columns; var_dump() will show you that you get the following for both fields:
["primary_key"]=>int(0)
This is as of PHP 5.2.13 and MySQL 5.0.51
krang at krang dot org dot uk ¶
18 years ago
The field type returns what PHP classifies the data found in the field, not how it is stored in the database; use the following example to retrieve the MySQL information about the field....
<?php
$USERNAME = '';
$PASSWORD = '';
$DATABASE = '';
$TABLE_NAME = '';
mysql_connect('localhost', $USERNAME, $PASSWORD)
or die ("Could not connect");
$result = mysql_query("SHOW FIELDS FROM $DATABASE.$TABLE_NAME");
$i = 0;
while ($row = mysql_fetch_array($result)) {
echo $row['Field'] . ' ' . $row['Type'];
}
?>
jorachim at geemail dot com ¶
11 years ago
If you want the fields in a table, a simple DESCRIBE query will work:
<?php
$query ="DESCRIBE Users";
$result = mysql_query($query);
echo "<ul>";
while($i = mysql_fetch_assoc($result))
echo "<li>{$i['Field']}</li>";
echo "</ul>";
?>
Should do the trick.
david at vitam dot be ¶
11 years ago
A little function to help coders to distinct the tablename from a multiselect query where some fields has the same name in differents tables.
<?php
public function sql($sql) {
$T_Return=array();
$result=@mysql_query($sql);
$i=0;
while ($i < mysql_num_fields($result)) {
$fields[]=mysql_fetch_field($result, $i);
$i++;
}
while ($row=mysql_fetch_row($result)) {
$new_row=array();
for($i=0;$i<count($row); $i++) {
$new_row[ $fields[$i]->table][$fields[$i]->name]=$row[$i];
}
$T_Return[]=$new_row;
}
return $T_Return;
}
?>
Nick Baicoianu ¶
14 years ago
Be sure to note that $max_length is the length of the longest value for that field in the returned dataset, NOT the maximum length of data that column is designed to hold.
Daniel B ¶
8 years ago
Simple function to display all data in a query...
function dumpquery($query) {
$numfields = mysql_num_fields($query);
echo '<table border="1" bgcolor="white"><tr>';
for ($i = 0; $i<$numfields; $i += 1) {
$field = mysql_fetch_field($query, $i);
echo '<th>' . $field->name . '</th>';
}
echo '</tr>';
while ($fielddata = mysql_fetch_array($query)) {
echo '<tr>';
for ($i = 0; $i<$numfields; $i += 1) {
$field = mysql_fetch_field($query, $i);
echo '<td>' . $fielddata[$field->name] . '</td>';
}
echo '</tr>';
}
echo '</table>';
}
lucien at ocia dot nl ¶
8 years ago
Performance Notes!
I used this script for testing, the table has 26 colums.
<?php
$t_start = microtime(true);
$sql = mysql_query("SELECT * FROM `table` LIMIT 1") or trigger_error(mysql_error(), E_USER_WARNING);
for ($i = 0; $i < mysql_num_fields($sql); $i++) {
$meta = mysql_fetch_field($sql, $i);
echo "Information for column ".$meta->name.":\n";
echo
"\tblob: $meta->blob
\tmax_length: $meta->max_length
\tmultiple_key: $meta->multiple_key
\tname: $meta->name
\tnot_null: $meta->not_null
\tnumeric: $meta->numeric
\tprimary_key: $meta->primary_key
\ttable: $meta->table
\ttype: $meta->type
\tunique_key: $meta->unique_key
\tunsigned: $meta->unsigned
\tzerofill: $meta->zerofill
";
}
$t_stop = microtime(true);
$t_proc = $t_stop - $t_start;
echo "processing time query 1: ".number_format($t_proc * 1000, 3)." ms\n";
unset($t_start);
unset($t_stop);
unset($t_proc);
$t_start = microtime(true);
$sql = mysql_query("DESCRIBE `table`");
while ($res = mysql_fetch_array($sql, MYSQL_ASSOC)) {
print_r($res);
}
$t_stop = microtime(true);
$t_proc = $t_stop - $t_start;
echo "processing time query 2: ".number_format($t_proc * 1000, 3)." ms\n";
?>
Query 1 => 0.444 ms
Query 2 => 1.146 ms
So for easy usage, Query 2 is advised... But if your a performance-geek, you should use Query 1.
php [spat] hm2k.org ¶
11 years ago
An improvement on the earlier mysql_column_exists function.
<?php
function mysql_column_exists($table_name, $column_name, $link=false) {
$result = @mysql_query("SHOW COLUMNS FROM $table_name LIKE '$column_name'", $link);
return (mysql_num_rows($result) > 0);
}
?>
mwwaygoo AT hotmail DOT com ¶
7 years ago
Using mysql_fetch_field you can produce a more robust version of mysql_fetch_assoc.
When querying 2 tables with the same field names, generally you would need to use mysql_fetch_row to get an integer key'ed array rather than an associated key'ed array. This is because fields of the same name in the second table will over-write the data returned from the first table.
However this simple function will insert the table name prior to the field name for the key and prevent cross-overs.
ie SELECT *, 'test' AS test 4 FROM table AS T_1, table AS T_2 WHERE T_1.a=T_2.b
could produce:
mysql_fetch_assoc() returns
array(
'index'=>2,
'a'=>'pear',
'b'=>'apple',
'test'=>'test',
4=>4
)
mysql_fetch_table_assoc() returns
array(
'T_1.index' =>1,
'T_1.a'=>'apple',
'T_1.b'=>'banana',
'T_2.index'=>2,
'T_2.a'=>'pear',
'T_2.b'=>'apple',
'test'=>'test',
4=>4
)
<?php
function mysql_fetch_table_assoc($resource)
{
// function to get all data from a query, without over-writing the same field
// by using the table name and the field name as the index
// get data first
$data=mysql_fetch_row($resource);
if(!$data) return $data; // end of data
// get field info
$fields=array();
$index=0;
$num_fields=mysql_num_fields($resource);
while($index<$num_fields)
{
$meta=mysql_fetch_field($resource, $index);
if(!$meta)
{
// if no field info then just use index number by default
$fields[$index]=$index;
}
else
{
$fields[$index]='';
// deal with field aliases - ie no table name (SELECT T_1.a AS temp)
if(!empty($meta->table)) $fields[$index]=$meta->table.'.';
// deal with raw data - ie no field name (SELECT 1)
if(!empty($meta->name)) $fields[$index].=$meta->name; else $fields[$index].=$index;
}
$index++;
}
$assoc_data=array_combine($fields, $data);
return $assoc_data;
}
?>
php at brayra dot com ¶
18 years ago
I needed to get the field information and the enum/set values. Here is the function I created to expand the object returned by mysql_fetch_field. I also, decided to return all the fields for a table in an array of field objects by "name" and position much like mysql_fetch_array does.
You could test it by using:
<?php
$myfields = GetFieldInfo('test_table');
print "<pre>";
print_r($myfields);
print "</pre>";
?>
The field objects now have 'len', 'values' and 'flags' parameters.
NOTE: 'values' only has data for set and enum fields.
<?php
//This assumes an open database connection
//I also use a constant DB_DB for current database.
function GetFieldInfo($table)
{
if($table == '') return false;
$fields = mysql_list_fields(DB_DB, $table);
if($fields){
$columns = mysql_query('show columns from ' . $table);
if($columns){
$num = mysql_num_fields($fields);
for($i=0; $i < $num; ++$i){
$column = mysql_fetch_array($columns);
$field = mysql_fetch_field($fields, $i);
$flags = mysql_field_flags($fields, $i);
if($flags == '') $flags=array();
else $flags = explode(' ',$flags);
if (ereg('enum.(.*).',$column['Type'],$match))
$field->values = explode(',',$match[1]);
if (ereg('set.(.*).',$column['Type'],$match))
$field->values = explode(',',$match[1]);
if(!$field->values) $field->values = array();
$field->flags = $flags;
$field->len = mysql_field_len($fields, $i);
$result_fields[$field->name] = $field;
$result_fields[$i] = $field;
}
mysql_free_result($columns);
}
mysql_free_result($fields);
return $result_fields;
}
return false;
}
?>
hope someone else finds this useful.
eviltofu at gmail dot com ¶
8 years ago
MYSQLI_TYPE_BLOB indicates the field is a BLOB or a TEXT. I think you would need to check the blob value. If its true then it's a BLOB, otherwise it's a TEXT. Can someone confirm?
dheep ¶
11 years ago
Simple PHP script for displaying the field names. Presuming the database is seleected already.
<?php
$sql = "SELECT * FROM table_name;";
$result = mysql_query($sql);
$i = 0;
while($i<mysql_num_fields($result))
{
$meta=mysql_fetch_field($result,$i);
echo $i.".".$meta->name."<br />";
$i++;
}
?>
OUTPUt:
0.id
1.todo
2.due date
3.priority
4.type
5.status
6.notes
hope this is useful.
