PHP local modification test OK, it won't work on the server. which expert can help me?

PHP local modification test OK, it will not work on the server. who can help me? The local test is acceptable, that is, it cannot be performed on the server, and there is no problem with the received value and connection. The following is the code written to the database. I think it is an error, but I cannot find the cause of the error. could you please take a look? Thank you ---------- split line ---------------- & lt ;? Phprequire_once (& quo PHP local modification test OK, it will not work on the server. who can help me?
The local test is acceptable, that is, it cannot be performed on the server, and there is no problem with the received value and connection. The following is the code written to the database. I think it is an error, but I cannot find the cause of the error. please take a look. thank you.
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Require_once ("../conn. inc. php"); // contains the database connection file
// Receives the form value
$ NetsId = $ _ GET ['id'];
// If ($ netsId = NULL ){
// $ NetsId = $ _ GET ['id'];
//} Else
If ($ _ GET ['id'] = NULL ){
Echo 'no modification information! ';
}
// Echo $ netsId;
$ User_name = $ _ POST ["user_name"];
$ User_psw = $ _ POST ["user_psw"];
$ User_ip = $ _ POST ["user_ip"];
$ Net_name = $ _ POST ["net_name"];
Echo $ net_name;
$ Net_url = $ _ POST ["net_url"];
$ Net_type = $ _ POST ["net_type"];
$ Province = $ _ POST ["Province"];
$ City = $ _ POST ['city'];
$ Net_content = $ _ POST ["net_content"];
// Pre-defined variable
$ Net_num = $ _ POST ["net_num"];
$ Net_in = $ _ POST ["net_in"];
$ Net_out = $ _ POST ["net_out"];
$ Net_ OK = $ _ POST ["net_ OK"];
$ Net_recom = $ _ POST ["net_recom"];

// System Time difference: 8 hours
Date_default_timezone_set ('Asia/Chongqing ');
$ Now = getdate (time ());
$ Cur_wday = $ now ['wday'];
$ Date = date ("Y-m-d H: I: s $ cweekday [$ cur_wday]");
$ Net_submit_time = date ("Y-m-d H: I: s ");
$ Last_time = $ _ POST ["last_time"];
If ($ City = NULL)
{
$ City = $ _ POST ['citydefault'];

}

// Enter the Operation statement
$ SQL = "UPDATE nets SET user_name = '$ user_name', user_psw = '$ user_psw', user_ip = '$ user_ip', net_name = '$ net_name ', net_url = '$ net_url', net_type = '$ net_type', Province = '$ Province', City = '$ City', net_content =' $ net_content ', net_num = $ net_num, net_in = $ net_in, net_out = $ net_out, net_ OK = $ net_ OK, net_recom = $ net_recom, net_submit_time = '$ others', last_time =' $ last_time 'where id = $ net_sid ";

Mysql_query ($ SQL); // pass the Operation statement to the mysql database
Echo "the website has been modified! ";
Echo 'You can also return to the home page or ';
Echo 'click to return ';
// Echo 'The modified ID' is '. $ netsId .'';

?>

------ Solution --------------------
Do not check function return values?
------ Solution --------------------
Send the error message.
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Discussion

Send the error message.

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Discussion

Reference:
Reference:

Send the error message.


Yes. send the error prompt. it is simple and quick.


Show this sentence, do not know what it means ......
The information is not successfully written into the database! You have an error in your SQL syntax; check the manual that corresponds to your MySQL server ve ......

------ Solution --------------------
Modify the SQL statement to this effect.
Id = {$ netsId }";