error on local mysql but not on RDS mysql - php

Question

I have a mysql insert query which runs on aws RDS(Live env) but throws an error on my local(local env).
on local I'am using mysql V-5.6
$sql = "INSERT INTO `users` (`id`,
`name`,
`email`,
`pass`)
values('','omi','omi#gmail.com','123123')
id is not null and auto_increment.
The error which i get on local is 'Incorrect integer value: '' for column 'id' at row 1'
but when this executed on live env all the data gets inserted into table.
I cant understand what exactly is happening here. please help. thank you.
DDL of users table.
local
CREATE TABLE `users`
`id` int(11) unsigned NOT NULL AUTO_INCREMENT,
`name` varchar(256) DEFAULT '',
`email` varchar(256) NOT NULL,
`pass` varchar(256) NOT NULL,
PRIMARY KEY (`id`)
) ENGINE=InnoDB AUTO_INCREMENT=25986 DEFAULT CHARSET=utf8;
Live
CREATE TABLE `users` (
`id` int(11) unsigned NOT NULL AUTO_INCREMENT,
`name` varchar(254) DEFAULT '',
`email` varchar(256) NOT NULL,
`pass` varchar(11) NOT NULL,
PRIMARY KEY (`id`)
) ENGINE=InnoDB AUTO_INCREMENT=26046 DEFAULT CHARSET=utf8;

Answer 1

I believe the error is with those quotes (''). When you want to do an insert with an auto_increment field, you have to use null as argument in the auto_increment field position.
See if this works:
$sql = "INSERT INTO `users`
(`id`, `name`, `email`, `pass`)
values(null,'omi','omi#gmail.com','123123');
EDIT 1
Using null doesn't generate any error because internally the DBMS is prepared to receive such an argument. It understands that is its duty to generate the next number of the sequence and if it hasn't any, 0 (of type integer in your case) is inserted first. I know defining "not null" in the DDL of a field and then using "null" in the DML insert statement for that exact field may look confusing, but it's just the right way to use the auto_increment feature.
From the documentation:
If the column is declared NOT NULL, it is also possible to assign NULL to the column to generate sequence numbers.
Also, if using an empty string as argument in an statement doesn't generate any error, it could maybe be because RDS interface has an internal function that converts empty to null. Something like the nullif function in MySQL.

Answer 2

You can't do it like that. Either dont even mention 'id' or give it null value.
$sql = "INSERT INTO `users` (
`name`,
`email`,
`pass`)
values('omi','omi#gmail.com','123123')
OR:
$sql = "INSERT INTO `users` (`id`,
`name`,
`email`,
`pass`)
values('NULL','omi','omi#gmail.com','123123')