Laravel migration: fields that defined as interger wil be treated as auto increment? - laravel

Question

Here is my code:
public function up()
{
Schema::create('sysmods', function (Blueprint $table) {
$table->increments('mod_id');
$table->string('mod_name','60');
$table->string('mod_alias_name','60');
$table->integer('mod_tb_id','6');// this will become auto increment?
$table->timestamps();
});
}
when i run the migrate command, it says:
" [PDOException]
SQLSTATE[42000]: Syntax error or access violation: 1075 Incorrect table def
inition; there can be only one auto column and it must be defined as a key"
Then as i check the sql, I found this:
(SQL: create table la_sysmods (mod_id int unsigned not null auto_increm
ent primary key, mod_name varchar(60) not null, mod_alias_name varchar(
60) not null, mod_tb_id int not null auto_increment primary key, created
_at timestamp null, updated_at timestamp null) default character set utf
8 collate utf8_unicode_ci)
The field 'mod_tb_id' which marked as integer has become increments. What's the problem? Thanks!

Answer 1

The second argument for the integer method is the autoIncrement variable. You need to remove it.
The Laravel method
public function integer($column, $autoIncrement = false, $unsigned = false)
{
return $this->addColumn('integer', $column, compact('autoIncrement', 'unsigned'));
}
Change this:
$table->integer('mod_tb_id','6');// this will become auto increment?
To this:
$table->integer('mod_tb_id');

Answer 2

You need to replace your
$table->integer('mod_tb_id','6');// this will become auto increment?
with
$table->integer('mod_tb_id')->length(6);
or
$table->integer('mod_tb_id', false, false)->length(6);
The second argument for integer() method is the flag for autoincrement and the third is for unsigned.
Hope it helps