INSERT with LEFT JOIN - php

Question

<?php
include 'connection.php';
session_start();
$noteinfo = array();
$noteinfo['note'] = $_POST['note'];
$_SESSION['noteinfo'] = $noteinfo;
if (isset($_POST['submit'])) {
if (empty($_POST['note'])) {
echo "Dobavete Komentar";
}
if (!empty($_SESSION['noteinfo'])) {
$check = mysqli_escape_string($conn,$_SESSION['userinfo']['fname']);
print_r($_SESSION['userinfo']);
$sql = "INSERT INTO users (user_fname,user_mname,user_lname,user_login,user_email,user_phone)
VALUES ('{$_SESSION['userinfo']['fname']}', '{$_SESSION['userinfo']['mname']}', '{$_SESSION['userinfo']['lname']}', '{$_SESSION['userinfo']['login']}', '{$_SESSION['userinfo']['email']}', '{$_SESSION['userinfo']['phone']}')";
$sql1 = "INSERT INTO addresses (address_line_1,address_line_2,address_zip,address_city,address_province,address_country)
VALUES ('{$_SESSION['addressinfo']['adr1']}', '{$_SESSION['addressinfo']['adr2']}', '{$_SESSION['addressinfo']['zip']}', '{$_SESSION['addressinfo']['city']}', '{$_SESSION['addressinfo']['provinciq']}', '{$_SESSION['addressinfo']['durjava']}')";
$sql2 = "INSERT INTO notes (note_text)
VALUES ('{$_SESSION['noteinfo']['note']}')";
$sql3 = "INSERT INTO users_addresses (ua_user_id,ua_address_id)
SELECT users.user_id,addresses.address_id
FROM ( VALUES () )";
if (mysqli_query($conn,$sql)) {
echo "Added";
if (mysqli_query($conn,$sql1)) {
echo "Added";
if (mysqli_query($conn,$sql2)) {
echo "Added";
if (mysqli_query($conn,$sql3)) {
echo "Mai stana toq put";
header("refresh:3 ; url=profile.php");
}
}
}
}
else{
echo "Error";
}
}
else{
header("refresh:1 ; url=zapiski.php");
}
}
?>
My question is for $sql3: I want when the forms are completed to fill the users_addresses with the id of the user and the id from the address tables.But for now the SQL doesn't fill nothing in the table users_addresses. These are my tables:

Answer 1

When a user is filling in values in an application and you need to look up ids for them, then a typical way to write the query looks like this:
INSERT INTO users_addresses (ua_user_id, ua_address_id)
VALUES ( (SELECT u.user_id FROM users u WHERE u.username = ?),
(SELECT a.address_id FROM address a WHERE a.address = ?)
);
That is, you are passing parameters into the query, using the parameters to look up ids, and then using those ids to insert into the junction table.

Answer 2

You seem to be missing the VALUES() function in your INSERT.
INSERT INTO users_addresses(ua_user_id,ua_address_id)
It should be,
INSERT INTO users_addresses(ua_user_id,ua_address_id) VALUES(some_variable,some_variable)
You could also do,
INSERT INTO users_addresses SET ua_user_id=some_variable, ua_address_id=some_variable
When it comes to selecting the data, you will need to JOIN your tables. I suggest a LEFT JOIN in this matter. It is important, that the id's that you are going to match against one another in the JOIN are coherent, so that you are able to link the tables together. It is then up to you whether you want a specific match or not in your condition, if you are parsing a user_id (i.e. WHERE clause).
Example selecting specific match:
SELECT
users_addresses.ua_id,
addresses.address_id
FROM
users_addresses
LEFT JOIN
users ON users_addresses.ua_user_id = users.user_id
LEFT JOIN
addresses ON users_addresses.ua_address_id = addresses.address_id
WHERE
users_addresses.ua_id = $some_id
Example selecting all matches:
SELECT
users_addresses.ua_id,
addresses.address_id
FROM
users_addresses
LEFT JOIN
users ON users_addresses.ua_user_id = users.user_id
LEFT JOIN
addresses ON users_addresses.ua_address_id = addresses.address_id
Let me know if this is what you are looking for, and whether you need something elaborated.
An important note, you should look into prepared statements since you are using the mysqli_* extension. It will improve your security a lot, as you are open to SQL-injections at the moment.