Reading and displaying Values from Sqlite3 Database with PHP - php

Question

I am writing a application that will read values from an SQlite3 database and display them through webbrowser with PHP. This is new to me and I have tried several things but can't seem to get it to work! The values are listed as REAL in the database, which should be PARAM_STR.
<?php
$db = new SQLite3('/home/pi/ECE522/test.db');
if(!$db) {
echo $db->lastErrorMsg();
} else {
echo "Opened DATABASE!";
$query = $db->prepare('SELECT df1, df2 FROM PLCValues');
$query->bindParm('df1', $df1,PDO::PARAM_STR);
$query->bindParm('df2', $df2,PDO::PARAM_STR);
$query->execute();
var_dump($df1);
var_dump($df2);
echo $df1;
echo $df2;
}
?>
On the webpage I get "Opened DATABASE!" but nothing else?
Thanks for any ideas!

Answer 1

You don't define the $df1 and $df2 before executing the query, that you bind as param at
$query->bindParm('df1', $df1,PDO::PARAM_STR);
$query->bindParm('df2', $df2,PDO::PARAM_STR);
Do you realy need that?
If you just want to select all values in columns 'df1' and 'df2' from PLCValues table, I think you need something like this:
$res = $db->query("SELECT df1, df2 FROM PLCValues");
while (($row = $res->fetchArray(SQLITE3_ASSOC))) {
var_dump($row);
}
For more information see examples from http://php.net/manual/ru/sqlite3stmt.bindparam.php
If you want to select values with certain df1, I think you need something like this:
$stmt = $db->prepare("SELECT df1, df2 FROM PLCValues WHERE df1=:df1");
$stmt->bindParam(':df1', '[WHAT_YOU_WANT_TO_SELECT]', [YOUR_DATA_TYPE]);
$result = $stmt->execute();
var_dump($result->fetchArray());