How to list specific data of a table, but using PDO ?
I'm starting to study and use PDO , but some things I can not find and that are well explained how to lite the data with a WHERE in the search.
MySQLi is used this way, but how to convert to PDO ??
$select = mysqli_query($conn,"SELECT * FROM 'tabela' WHERE 'valor1' = '$var_1' AND 'valor2' = '$var_2'");
$aRow = mysqli_fetch_assoc($quti_mh);
$idt = $aRow['id'];
To make a simple query with fixed parameters or without them you can use the query () method does exactly the same thing as mysqli_query () ie it processes a query and returns a resultset that should be manipulated to extract the values.
The method that returns the database information is fetch*() it has several flavors . , arrays and objects are favorites.
fetch ()
When you need to return only one record (either to make a "change / edit") prefer fetch() it returns an array / object in the 'correct' structure do not do something like, echo $usuario[0]['nome'] , just% / p>
Return structure:
Array
(
[id] => 1
[nome] => Doge
[senha] => ***
)
fetchAll ()
To return all rows of a query use $usuario['nome'] is recommended in case where there are few records.
Return structure
Array
(
[0] => Array
(
[id] => 1
[nome] => Doge
[senha] => ***
)
)
fetchColumn ()
Returns a scalar (ie a pure value like int, string, float etc are left out of this list arrays objects and other compound types) of a records, accepts an argument that is the index of the query column.
$db = new PDO('mysql:host=localhost;dbname=teste', 'usuario', 'senha');
//* = id, nome e senha
$query = $db->query("SELECT * FROM usuarios WHERE ativo = 1 limit 300");
$resultado = $query->fetchAll(PDO::FETCH_ASSOC);
foreach($resultado as $item){
$item['nome'];
}
To avoid problems with sql injection prepared statements are the solution because the values sent by the user are not placed directly in the sql statement, for more details see this
$db = new PDO('mysql:host=localhost;dbname=teste', 'usuario', 'senha');
$stmt = $db->prepare("SELECT * FROM usuarios WHERE id = ?");
if(!$stmt->execute()){
echo '<pre>';
print_r($stmt->errorInfo());
}
$resultado = $stmt->fetch(PDO::FETCH_ASSOC);
I think I understand what you mean, is that what you want?
$tables = $dbh->prepare("SELECT * FROM 'tabela' WHERE 'valor1' = ? AND 'valor2' = ?");
$tables->execute(array('apple', 'green'));
$resultados = $tables->fetch(PDO::FETCH_ASSOC);