Sessions in PHP

Question

PHP

This is not the first time I have encountered such a problem, but on this project they were needed at the request of the customer. On hosting, sessions do not work for a cut.
I write this simple code:

<?php
session_start();
if (!isset($_SESSION['counter'])) $_SESSION['counter']=0;
echo "Вы обновили эту страницу ".$_SESSION['counter']++." раз. ";
echo "<br><a href=".$_SERVER['PHP_SELF'].">обновить</a><br>";
?>

And he doesn't want to work. Here are the server settings regarding sessions

Session Support	enabled
Registered save handlers	files user memcache sqlite
Registered serializer handlers	php php_binary wddx

Directive	local value	Master Value
session.auto_start	Off	Off
session.bug_compat_42	On	On
session.bug_compat_warn	On	On
session.cache_expire	180	180
session.cache_limiter	nocache	nocache
session.cookie_domain	no value	no value
session.cookie_httponly	Off	Off
session.cookie_lifetime	0	0
session.cookie_path	/	/
session.cookie_secure	Off	Off
session.entropy_file	no value	no value
session.entropy_length	0	0
session.gc_divisor	100	100
session.gc_maxlifetime	1440	1440
session.gc_probability	one	one
session.hash_bits_per_character	4	4
session.hash_function	0	0
session.name	PHPSESSID	PHPSESSID
session.referer_check	no value	no value
session.save_handler	files	files
session.save_path	/tmp/php_sess	/tmp/php_sess
session.serialize_handler	php	php
session.use_cookies	On	On
session.use_only_cookies	Off	Off
session.use_trans_sid	0	0

Answer 1

if after that
if (!isset($_SESSION['counter'])) $_SESSION['counter']=0;
do
var_dump($_SESSION);
what outputs?

Answer 2

Before <? php no empty spaces? bom characters for example? Session number cookies may not go away if so.
Is the time on the server correct? Session number cookies can be deleted immediately if so.

Answer 3

You can check if php has write permissions to session.save_path. Ever since. Have you contacted hosting support?

Answer 4

Comment. Superfluous ... In theory, it should initialize and add one automatically ...
//if (!isset($_SESSION['counter'])) $_SESSION['counter']=0;

Answer 5

2 options:
1:
SELECT
t2.*
FROM t1 INNER JOIN t2 ON t1.id = t2.owner_id
2.
SELECT
t2.*
FROM t2 WHERE t2.owner_id IN (SELECT t1.id FROM t1)
Learn the materiel :)