It is probably worth pointing out that the array elements will actually be of type string, OR NULL if the field is null in the database.
Thus, either use a double equal comparison to look for empty or null
Or, use a triple equal comparison to be able to distinguish the two cases
e.g.
if ($field === '') echo "Empty, not NULL\n";
if ($field === NULL) echo "NULL\n";
if ($field == '') echo "Empty or NULL\n";
mysql_fetch_row
(PHP 4, PHP 5)
mysql_fetch_row — Get a result row as an enumerated array
Această extensie este dezaprobată începând cu PHP 5.5.0 și va fi eliminată în viitor. În locul ei trebuie utilizate extensiile MySQLi sau PDO_MySQL. Vedeți de asemenea ghidul MySQL: selectarea unei API și FAQ asociat pentru mai multe informații. Alternative ale acestei funcții includ:
Descrierea
$result
)Returns a numerical array that corresponds to the fetched row and moves the internal data pointer ahead.
Parametri
-
result -
Rezultatul de tip resource, care este evaluat. Acest rezultat provine de la apelul funcției mysql_query ().
Valorile întoarse
Returns an numerical array of strings that corresponds to the fetched row, or
FALSE if there are no more rows.
mysql_fetch_row() fetches one row of data from the result associated with the specified result identifier. The row is returned as an array. Each result column is stored in an array offset, starting at offset 0.
Exemple
Example #1 Fetching one row with mysql_fetch_row()
<?php
$result = mysql_query("SELECT id,email FROM people WHERE id = '42'");
if (!$result) {
echo 'Could not run query: ' . mysql_error();
exit;
}
$row = mysql_fetch_row($result);
echo $row[0]; // 42
echo $row[1]; // the email value
?>
Note
Notă: Această funcție stabilește câmpurile NULL la valoarea PHP
NULL.
Vedeți de asemenea
- mysql_fetch_array() - Fetch a result row as an associative array, a numeric array, or both
- mysql_fetch_assoc() - Fetch a result row as an associative array
- mysql_fetch_object() - Fetch a result row as an object
- mysql_data_seek() - Move internal result pointer
- mysql_fetch_lengths() - Get the length of each output in a result
- mysql_result() - Get result data
to print an array, simply use print_r(array name)
like this:
$myrow = mysql_fetch_row($result);
echo "<pre>";
print_r($myrow);
echo "</pre>";
this will output the array in a readable form, with the index, too. Don't forget the 'pre' tags or the output will be on a single line.
The following are the basic codes to get a specific row from the mysql db into a $row variable:
$query = "SELECT * FROM table";
$result = mysql_query($query);
$row = mysql_fetch_row($result);
And $row[0], $row[1] ... $row[n] are used to access those field values.
Does anyone know how I can add a new field to $row, so that the field count increases from n to n+1?
I have tried treating $row like an array, and tried array_push function, but didn't work.
Thanks.
The following function to read all data out of a mysql-resultset, is may be faster than Rafaels solution:
<?
function mysql_fetch_all($result) {
while($row=mysql_fetch_array($result)) {
$return[] = $row;
}
return $return;
}
?>
Maybe worth pointing out that all the fields returned by this (and other?) calls are returned with type string. This had me puzzled for quite some time.
<?php
require 'prhlavicka.php';
pis_hlavicku('Vypis článků');
require_once 'db.php';
$kom = new server();
$sql=$kom->query("SELECT autor,nazev,obsah FROM `Clanky_Sadek`");
while ($data = mysql_fetch_row($sql)){
ECHO '<br />--AUTOR--<br />'.$data[0].'<br />__NÁZEV ČLÁNKU__<br />'.$data[1].'<br />..OBSAH ČLÁNKU..<br />'.$data[2]; }
include 'Paticka.html'; ?>
<?php
require_once'db.php';
mysql_query("set names 'utf8'");
$vysledek=mysql_query("SELECT*FROM `test`") ;
while($zaznam = mysql_fetch_row($vysledek)):
echo $zaznam[0]."<br>";
echo $zaznam[1]."<br>";
endwhile;
?>
If you need to quickly just grab all of a particular column (for example, with a "SELECT DISTINCT a FROM x" query), this quick function will just slice through and fetch an array of the resultant values:
<?
function mysql_slice($query, $colNo=0) {
// Return an array of single columns
if(gettype($query) == 'string') {
$sql = mysql_query($query) or die(mysql_error());
} else {
$sql = $query;
var_dump($query);
}
$array = array();
for($i = 0; $i < mysql_num_rows($sql); $i++) {
$array[] = mysql_result($sql, $i, $colNo);
}
mysql_free_result($sql);
return $array;
}
?>
To use it:
<?
foreach(mysql_slice("SELECT DISTINCT field FROM table") AS $x) {
echo "{$x}\n";
}
// OR
$array = mysql_slice("SELECT DISTINCT field FROM table");
var_dump($array);
?>
Creates table from all db info:
<?php
$qry = "SELECT * FROM exp_member_data";
$res = mysql_query($mem_qry);
function mysql_fetch_all($res) {
while($row=mysql_fetch_array($res)) {
$return[] = $row;
}
return $return;
}
function create_table($dataArr) {
echo "<tr>";
for($j = 0; $j < count($dataArr); $j++) {
echo "<td>".$dataArr[$j]."</td>";
}
echo "</tr>";
}
$all = mysql_fetch_all($res);
echo "<table class='data_table'>";
for($i = 0; $i < count($all); $i++) {
create_table($all[$i]);
}
echo "</table>";
?>
sry :) note now fixed:
<?php
$esi=mysql_list_tables($db);$ris=mysql_fetch_row($esi);
//example: $db has >= 1 tabs
echo var_dump($ris);
//echoes only array(1). solution:
while($ris=mysql_fetch_row($esi)) echo $ris[0];
/*debug:
$ris=array("1st_tab"); ... $ris=array("n_tab");$ris=false;*/
while ($ris[]=mysql_fetch_row($esi));
//debug:$ris=array(array("1st_tab"), ... array("n_tab"));
echo $ris[n][0];//echo:"n_tab"
echo $ris[0][n];//echo:array | null
?>
hope it helps
