How to fetch and display an array using PDO? - arrays

Question

I understand there are MANY ways to do all of this, but trying to do it the best way.
I have created the db parameters, dns, dbh, sth, sql and generally quite happy with the result up to ... well ... the result part.
<?php
// db parameters
$dbhost = "localhost";
$dbname = "x";
$dbuser = "y";
$dbpass = "z";
// driver invocation (dsn is short for data source name)
$dsn = "mysql:host=$dbhost;dbname=$dbname";
// create db object (dbh is short for database handle)
$dbh = new PDO($dsn, $dbuser, $dbpass);
// execution of database query (sth is short for statement handle)
$sql = "SELECT * FROM a_aif_remaining";
$sth = $dbh->prepare($sql);
$sth->execute();
NOT SURE WHAT TO PUT BELOW.... (A) or (B)
I just want to present a simple array of the data. One row from the table per line.
Option A
echo $_POST['fieldname1'];
echo $_POST['fieldname2'];
echo $_POST['fieldname3'];
Option B
while ($rows = $sth->fetch(PDO::FETCH_ASSOC)) {
echo $row[fieldname1],'<br>';
}
AND I AM CONFIDENT WITH THE ENDING
$dbh = NULL;
?>
Any advise would be GREATLY appreciated.
UPDATED CODE: (Produces nothing on the page)
<?php
// db parameters
$dbhost = "localhost";
$dbname = "theaudit_db1";
$dbuser = "theaudit_user";
$dbpass = "audit1999";
$dsn = "mysql:host=$dbhost;dbname=$dbname"; // driver invocation (dsn is short for Data Source Name)
try {
$dbh = new PDO($dsn, $dbuser, $dbpass); // connect to new db object (dbh is short for Database Handle)
$dbh->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION); // set the PDO error mode to enable exceptions
$dbh->setAttribute(PDO::ATTR_EMULATE_PREPARES, false); // set the PDO emulate prepares to false
// execute query to database (sth is short for Statement Handle)
$sql = "SELECT * FROM a_aif_remaining";
$sth = $dbh->prepare($sql);
$sth->execute();
$data = $sth->fetchAll(PDO::FETCH_ASSOC);
$dbh = NULL;
}
catch(PDOException $e)
{
echo $e->getMessage();
}
?>

Answer 1

Though I can't get what's the connection between A anb B, I can answer the
I just want to present a simple array of the data. One row from the table per line.
question.
$sql = "SELECT * FROM a_aif_remaining";
$sth = $dbh->prepare($sql);
$sth->execute();
$data = $sth->fetchAll(PDO::FETCH_ASSOC);
where $data is a sought-for array.

Answer 2

The problem with your updated code is simple - you arent echo'ing your data out. You need to add something like..
foreach($data as $arKey=>$dataRow){
foreach($dataRow as $arKey=>$rowField){
echo $rowField.','; //concat with a ',' to give csv like output
}
echo '<br>'; //to get to next line for each row (may want to trim the last ','
}
I am also confused by the reference to $_POST. It is true both are associate arrays but that does not mean that the $_POST option is viable - the data would only be available in the $_POST if you put it there (eg $_POST = $data) which would be pointless. Or if you had posted the data from somewhere else. Neither seem to fit what you are asking so I would forget about the $_POST and just figure out how you access your multi dimensional $data array. There is endless tut's on this subject. Try using
var_dump($data)
to see whats inside that should help you visualise what is going on.
NOTE: in option B you are not correctly concatenating or referencing your array it should be:
while ($rows = $sth->fetch(PDO::FETCH_ASSOC)) {
echo $rows[fieldname1].'<br>'; //$row doesnt exist its $rows and you use . to concat not ,
}
Ah yes and probably better to use unset rather than setting $dbh to equal null
unset($dbh);