SELECT colonne1, colonne2, ...
FROM table1, table2, ...
WHERE colonnei=valeuri
AND|OR [NOT] colonnek IN (val1, val2, ...)
AND (colonnel BETWEEN aa AND bb)
AND colonnef LIKE "%$chaîne%"
ORDER BY colonnei ASC|DESC
GROUP BY colonnej
LIMIT a, b

if($db = mysql_connect($host, $user, $pass)) {
    if($dbb = mysql_select_db($base)) {
        ...
        mysql_close();
    } else {
        die("connexion à la base $base impossible");
    }
} else {
    die("connexion au serveur $host impossible");
}

$db1 = @mysql_connect("localhost" , "root" , "password");
$db2 = @mysql_connect("localhost" , "root" , "password" , true);

$result = mysql_query("SELECT * FROM user") or die("erreur de base de données");
echo "Il y a ".mysql_num_rows($result)."résultats.";

$result = mysql_query("SELECT COUNT(*) FROM user") or die("erreur de base de données");
$ligne = mysql_fetch_row($result);
echo "Il y a ".$ligne[0]."résultats.";

Define("MYSQL_HOST", "localhost");
Define("MYSQL_USER", "root");
Define("MYSQL_PWD", "");
$connect = mysql_connect(MYSQL_HOST, MYSQL_USER, MYSQL_PWD);
$db = mysql_query("SHOW DATABASES;");
while($db_array = mysql_fetch_row($db)) {
    echo $db_array[0]."<br >";
}
mysql_close($connect);

Define("MYSQL_HOST", "localhost");
Define("MYSQL_USER", "root");
Define("MYSQL_PWD", "");
$connect = mysql_connect(MYSQL_HOST, MYSQL_USER, MYSQL_PWD);
$db = mysql_list_dbs($connect);
while($db_array = mysql_fetch_row($db)) {
    echo $db_array[0]."<br />";
}
@mysql_close($connect);

Define("MYSQL_HOST", "localhost");
Define("MYSQL_USER", "root");
Define("MYSQL_PWD", "");
Define("MYSQL_BDD", "ma_base_de_données"); //Changez ici la valeur
$connect = mysql_connect(MYSQL_HOST, MYSQL_USER, MYSQL_PWD);
mysql_select_db(MYSQL_BDD, $connect); //On sélectionne la base de données
$tables = mysql_query("SHOW TABLES;");
while($tables_array = mysql_fetch_row($tables)) {
    echo $tables_array[0]."<br />";
}
mysql_close($connect);

Define("MYSQL_HOST", "localhost");
Define("MYSQL_USER", "root");
Define("MYSQL_PWD", "");
Define("MYSQL_BDD", "ma_base_de_données"); //Changez ici la valeur
$connect = mysql_connect(MYSQL_HOST, MYSQL_USER, MYSQL_PWD);
$tables = mysql_list_tables(MYSQL_BDD);
while($tables_array = mysql_fetch_row($tables)) {
    echo $tables_array[0]."<br />";
}
mysql_close($connect);

mysql_query("UPDATE `table` SET `col`='value' WHERE `id`=$id; DELETE FROM `table` WHERE `id`=$id2");

mysql_query("UPDATE `table` SET `col`='value' WHERE `id`=$id");
mysql_query("DELETE FROM `table` WHERE `id`=$id2");

SELECT lastmodified
FROM citations
WHERE id=$id;

$requet = "SELECT lastmodified FROM citations WHERE id=$id";
if($result = mysql_query($requet)) 
{
    if($ligne = mysql_fetch_row($result)) 
	{
        $lastmodifed = $ligne[0];
    } 
	else 
        die("Erreur base de données");
} 
else 
    die("Erreur base de données");

list($date, $time) = explode(" ", $lastmodified);

list($year, $month, $day) = explode("-", $date);

list($hour, $min, $sec) = explode(":", $time);

echo $lastmodified = "$day/$month/$year $time";

$months = array("janvier", "février", "mars", "avril", "mai", "juin",
    "juillet", "août", "septembre", "octobre", "novembre", "décembre");

echo $lastmodified = "le $day ".$months[$month-1]." $year à ${hour}h${min}m${sec}s";

$dateMySQL = "2006-28-12 22:45:34";
$echo date("d/m/Y H:i:s", strtotime($dateMySQL)); //Affiche 28/12/2006 22:45:34

date +/- INTERVAL valeur unité

SELECT
FROM
WHERE `date` BETWEEN ('2003-06-25' - INTERVAL 3 MONTH) AND '2003-06-25'

$select_annee=mysql_query("SELECT DISTINCT YEAR(DATE) as Annee FROM table1 WHERE id = '$id'"); 
while($annee = mysql_fetch_array($select_annee))
{
  echo $annee['Annee'];
}

<?php
define("MYSQL_HOST", "localhost");
define("MYSQL_USER", "root");
define("MYSQL_PWD", "");
define("MYSQL_BDD", "ma_base_de_données");

$db = @mysql_connect(MYSQL_HOST, MYSQL_USER, MYSQL_PWD);
@mysql_select_db(MYSQL_BDD, $db);
$query = "SELECT * FROM team ORDER BY id";
$result = @mysql_query($query);
while($row = @mysql_fetch_assoc($result)) {
    //... et on arrive ainsi au dernier enregistrement renvoyé par la requête
}

// On se repositionne sur le premier enregistrement
@mysql_data_seek($result, 0); 
// On se replace sur le premier enregistrement
$row = @mysql_fetch_assoc($result); // Il faut le relire
//On peut manipuler l'enregistrement $row["mon_champ"]
?>

<?php
define("MYSQL_HOST", "localhost");
define("MYSQL_USER", "root");
define("MYSQL_PWD", "");
define("MYSQL_BDD", "ma_base_de_données");

$db = @mysql_connect(MYSQL_HOST, MYSQL_USER, MYSQL_PWD);
@mysql_select_db(MYSQL_BDD, $db);
$query = "SELECT * FROM team ORDER BY id";
$result = @mysql_query($query);
$nb_row = @mysql_num_rows($result);

@mysql_data_seek($result, $nb_row - 1); //On se place sur le dernier enregistrement
$row = @mysql_fetch_assoc($result); //Il faut le relire
// On peut manipuler l'enregistrement : $row["mon_champ"];
?>

SELECT *
FROM nomTable
ORDER BY RAND()
LIMIT 1

Warning: mysql_fetch_assoc(): supplied argument is not a valid MySQL result resource in /var/www/html/bugMySQL.php on line 10

 1 <?php
 2 
 3 $connexion = mysql_connect('localhost', 'root', '');
 4 
 5 mysql_select_db('test', $connexion);
 6
 7 $requete = 'SELECT * FROM nomTable WHERE champ = ';
 8 $resultat = mysql_query($requete, $connexion);
 9 
10 while ($ligne = mysql_fetch_assoc($resultat)) {
11     echo "{$ligne['champ']}<br/>";
12 }
13 
14 ?>

<?php

$connexion = mysql_connect('localhost', 'root', '') or exit(mysql_error());

mysql_select_db('test', $connexion) or exit(mysql_error());

$requete = 'SELECT * FROM nomTable WHERE champ = ';
$resultat = mysql_query($requete, $connexion) or exit(mysql_error() . "<br/>$requete");

while ($ligne = mysql_fetch_assoc($resultat)) {
    echo "{$ligne['champ']}<br/>";
}

?>

You have an error in your SQL syntax near '' at line 1
SELECT * FROM nomTable WHERE champ =

<?php
 
// Inclure dans vos scripts PHP avant tout envoi d'HTML
header ('Content-type: text/html; charset=utf-8');
 
// Pour tester que PHP renvoie les caractères correctement (vous pouvez mettre tous les caractères
// que vous souhaitez dans le echo ci-dessous, l'utf-8 est prévu pour être multilingue
echo 'é à € û ü';
 
?>

mysql_query("SET NAMES 'utf8'");

mysql_connect($dbhost, $dblogin, $dbpass) ;