The Documentation doesn't mention this, but you can use a fetch style as a second parameter. For example:
<?php
$data=$pdo->query($sql,PDO::FETCH_NUM);
foreach($data as $row) {
// etc
}
?>
(PHP 5 >= 5.1.0, PHP 7, PECL pdo >= 0.2.0)
PDO::query — 执行 SQL 语句，以 PDOStatement 对象形式返回结果集
$statement
, int $PDO::FETCH_CLASS
, string $classname
, array $ctorargs
) : PDOStatementPDO::query() 在单次函数调用内执行 SQL 语句，以 PDOStatement 对象形式返回结果集（如果有数据的话）。
如果反复调用同一个查询，用 PDO::prepare() 准备 PDOStatement 对象，并用 PDOStatement::execute() 执行语句，将具有更好的性能。
如果没有完整获取结果集内的数据，就调用下一个 PDO::query()，将可能调用失败。 应当在执行下一个 PDO::query() 前，先用 PDOStatement::closeCursor() 释放数据库PDOStatement 关联的资源。
Note:
如果传入函数的参数数量超过一个，多余的参数将相当于调用结果对象 PDOStatement::setFetchMode() 方法。
PDO::query() 返回 PDOStatement 对象，或在失败时返回 FALSE。
Example #1 展示 PDO::query 的使用
PDO::query() 一个不错的功能是：执行 SELECT 语句，并能够循环遍历结果集。
<?php
function getFruit($conn) {
$sql = 'SELECT name, color, calories FROM fruit ORDER BY name';
foreach ($conn->query($sql) as $row) {
print $row['name'] . "\t";
print $row['color'] . "\t";
print $row['calories'] . "\n";
}
}
?>
以上例程会输出：
apple red 150 banana yellow 250 kiwi brown 75 lemon yellow 25 orange orange 300 pear green 150 watermelon pink 90
The Documentation doesn't mention this, but you can use a fetch style as a second parameter. For example:
<?php
$data=$pdo->query($sql,PDO::FETCH_NUM);
foreach($data as $row) {
// etc
}
?>
Connecting
==============================
<?php
try{
$db = new PDO("dbtype:host=yourhost;dbname=yourdbname;charset=utf8","username","password");
/*Other Codes*/
}catch(PDOException $e ){
echo "Error: ".$e;
}
?>
Excute query with secure data
==============================
<?php
try{
$db = new PDO("dbtype:host=yourhost;dbname=yourdbname;charset=utf8","username","password");
$mysecuredata=14;
$db->query("Select * from table where id=".$mysecuredata);
}catch(PDOException $e ){
echo "Error: ".$e;
}
?>
Excute query with insecure data
==============================
<?php
try{
$db = new PDO("dbtype:host=yourhost;dbname=yourdbname;charset=utf8","username","password");
$myinsecuredata=$_GET["id"];
$query=$db->prepare("Select * from table where id=?");
$query->excute(array($myinsecuredata));
}catch(PDOException $e ){
echo "Error: ".$e;
}
?>
Getting Data in database
==============================
<?php
try{
$db = new PDO("dbtype:host=yourhost;dbname=yourdbname;charset=utf8","username","password");
$myinsecuredata=$_GET["table"];
$query=$db->prepare("Select * from ?");
$query->excute(array($myinsecuredata));
while($row=$query->fetch(PDO::FETCH_OBJ)) {
/*its getting data in line.And its an object*/
echo $row->yourcolumnname;
}
}catch(PDOException $e ){
echo "Error: ".$e;
}
?>
Reference
==============================
http://gencbilgin.net/pdo-kullanimi-php-de-veritabani-islemleri.html
Trying to pass like second argument PDO::FETCH_ASSOC it still work.
So passing FETCH TYPE like argument seems work.
This save you from something like:
<?php
$result = $stmt->setFetchMode(PDO::FETCH_NUM);
?>
Example:
<?php
$res = $db->query('SELECT * FROM `mytable` WHERE true', PDO::FETCH_ASSOC);
?>
If you are using PDO to create an SQLite dbfile that will be used by an Android application, you can set common values via the $dbh->query("PRAGMA ...") statement;
a tipical example would be the user_version of the database or the page_size
<?php
...
$dbh = new PDO($PDO_DSN, null, null, null);
$dbh->query("PRAGMA page_size = 4096"); //Android match page size
$dbh->query("PRAGMA user_version = 2"); //This match super(context, DB_NAME, null, DB_VERSION) of the DatabaseOpenHelper
....
?>
After a lot of hours working with DataLink on Oracle->MySQL and PDO we (me and Adriano Rodrigues, that solve it) discover that PDO (and oci too) need the attribute AUTOCOMMIT set to FALSE to work correctly with.
There's 3 ways to set autocommit to false: On constructor, setting the atribute after construct and before query data or initiating a Transaction (that turns off autocommit mode)
The examples:
<?php
// First way - On PDO Constructor
$options = array(PDO::ATTR_AUTOCOMMIT=>FALSE);
$pdo = new PDO($dsn,$user,$pass,$options);
// now we are ready to query DataLinks
?>
<?php
// Second Way - Before create statements
$pdo = new PDO($dsn,$user,$pass);
$pdo->setAttribute(PDO::ATTR_AUTOCOMMIT,FALSE);
// or
$pdo->beginTransaction();
// now we are ready to query DataLinks
?>
To use DataLinks on oci just use OCI_DEFAULT on oci_execute() function;
If someone is suffering of the "MySQL server has gone away" problem after executing multiple queries, this is a solution that solved it for me. It's similar to the one needed for the exact same problem in mysqli.
<?php
$stmt=$db->prepare($query);
$stmt->execute();
do { $stmt->fetch(); $stmt->closeCursor(); ++$line; } while($stmt-
>nextRowset());
?>
I found this only works using prepare and execute this way, not if you
directly execute the query with query().
I found this method extremely useful for getting the iteration count. Note the usage of "for" instead of "while" or "foreach". Just place the "$row = $query->fetch()" as the second condition of your for loop (which is do until). This is the best of both worlds IMHO. Criticism welcome.
try {
$hostname = "servername";
$dbname = "dbname";
$username = "username";
$pw = "password";
$pdo = new PDO ("mssql:host=$hostname;dbname=$dbname","$username","$pw");
} catch (PDOException $e) {
echo "Failed to get DB handle: " . $e->getMessage() . "\n";
exit;
}
$query = $pdo->prepare("select name FROM tbl_name");
$query->execute();
for($i=0; $row = $query->fetch(); $i++){
echo $i." - ".$row['name']."<br/>";
}
unset($pdo);
unset($query);
The handling of errors by this function is controlled by the attribute PDO::ATTR_ERRMODE.
Use the following to make it throw an exception:
<?php
$dbh->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);
?>
Please note that when Query() fails, it does not return a PDOStatement object . It simply returns false.
> When query() fails, the boolean false is returned.
I think that is "Silent Mode".
If that set attribute ErrorMode "Exception Mode"
then that throw PDOException.
$pdoObj = new PDO( $dsn, $user, $pass );
$pdoObj->setAttribute("PDO::ATTR_ERRMODE", PDO::ERRMODE_EXCEPTION);