Try to adopt JSON in database because i have data not fixed. i can query well from terminal, and need to write same query to php script. i have spent a lot of time before ask. example:
sqlite> select json_extract(events.interni, '$') from events WHERE id='35';
output
[{"student_id":"12","student_name":"Lisa Ochoa"},{"student_id":"21","student_name":"Rafael Royal"}]
where id = 35 will become a variable of $ _POST ['id']
what I tried:
$result2 = $db->query("select json_extract(events.interni, '$') from events WHERE id='35'");
var_dump($result2->fetchAll(PDO::FETCH_ASSOC));
return [] <- empty array
i want instead = [{"student_id":"21","student_name":"Rafael Royal"}]
where did I go wrong?
I followed this answer on SO https://stackoverflow.com/a/33433552/1273715 but i need to move the query in php for an ajax call
possibile another help.
Can the result fron $ajax call can be usable as key value or remain string? in other hands i can convert string to object like students = new Object()?
eaxaple of what i need in js environment - count objects in array - and loop key value
var data = [{"student_id":"12","student_name":"Lisa Ochoa"},{"student_id":"21","student_name":"Rafael Royal"}]
consolle.log(JSON.Stringify(data));
here I would like to avoid the backslash
consolle.log(JSON.Stringify(data.lenght));
in this phase the desired data is = 2
any possible help is largely appreciated
UPDATE
leave json_extract() function i have solved the second problem, so now i can work whit object property, and finally important to count objects in array:
<?php
try {
$db = new PDO('sqlite:eventi.sqlite3');
$db->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);
}
catch (PDOException $e) {
echo "I'm sorry, Dave. I'm afraid I can't do that.";
echo $e->getMessage();
}
$risultato = $db->query("SELECT * FROM events WHERE id = '35'", PDO::FETCH_ASSOC);
$result = array();
foreach ($risultato as $row) {
$result[] = $row;
}
// echo "Results: ", json_encode($result), "\n"; this produced backslash
echo $result[0]['interni'];
?>
js part
var num='';
$.ajax({
url: "sqlitedb/test-con.php",
type: 'POST',
dataType: 'json',
success:function(result){
console.log(result[0].student_id+ " - "+ result[0].student_name); // output here is good: 12 - Lisa Ochoa
counter(Object.keys(result).length);
}});
function counter (numero){
console.log("num2: =" + numero);
}
//out put here: 2
perfect!
odd behaviour:
console.log(result[0].student_id+ " - "+ result[0].student_name);
12 - Lisa Ochoa
outup is right but
console.log(result.lenght);
output is null
You are surrounding you query with double quotes but inside the query there is an unescaped $
.
Try escaping it:
$result2 = $db->query("SELECT json_extract(events.interni, '\$') FROM events WHERE id='35'");
var_export($result2->fetchAll(PDO::FETCH_ASSOC));
You can try something like this. and since you said in the comment about approaching it with ajax. I have included that also.
I also include php mysql backend workability for clarity. so Yo have now two options
1.) PHP WITH MYSQL
2.) PHP WITH SQLITE as you requested
index.html
<script src="jquery-3.1.1.min.js" type="text/javascript"></script>
<script type="text/javascript">
$(document).ready(function(){
$.ajax({
type: 'get',
url: 'data.php',
dataType: 'JSON',
cache:false,
success: function(data){
var length = data.length;
for(var s=0; s<length; s++){
var student_id = data[s].student_id;
var student_name = data[s].student_name;
var res = "<div>" +
"<b>student_id:</b> " + student_id + "<br>" +
"<b>student_name:</b> " + student_name + "<br>" +
"</div><br>";
$("#Result").append(res);
}
}
});
});
</script>
<body>
<div id="Result" ></div>
</body>
In mysql database you can do it this way.
<?php
$host = "localhost";
$user = "ryour username";
$password = "your password";
$dbname = "your bd name";
$con = mysqli_connect($host, $user, $password,$dbname);
// Check connection
if (!$con) {
echo "cannot connect to db";
}
$return_arr = array();
$query = "SELECT id, student_id, student_name FROM events where id='35'";
$result = mysqli_query($con,$query);
while($row = mysqli_fetch_array($result)){
$student_id = $row['student_id'];
$student_name = $row['student_name'];
$return_arr[] = array("student_id" => $student_id,
"student_name" => $student_name);
}
// Encoding array in JSON format
echo json_encode($return_arr);
?>
So with sqlitedb something like this will work for you
$return_arr = array();
$result2 = $db->query("SELECT id, student_id, student_name FROM events where id='35'");
$result2->execute(array());
//$result2 = $db->query("SELECT * FROM events where id='35'");
//$result =$result2->fetchAll(PDO::FETCH_ASSOC));
while($row = $result2->fetch()){
$student_id = $row['student_id'];
$student_name = $row['student_name'];
$return_arr[] = array("student_id" => $student_id,
"student_name" => $student_name);
}
// Encoding array in JSON format
echo json_encode($return_arr);
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