Laravel 5.2 Unique Validation always invalidate on UPDATE - php

Question

I have been trying to figure this one out for quite a whiale and have gone through every post from here and Laracast to figure this out but in vein.
I have done this before and it worked but I am not quite sure why it doesn't now.
Basically setting up a rule in your form request should follow the format below:
<?php
class MyFormRequest extends Request{
public function rules(){
return [
'field' => 'required|unique:table_name:field,' . $this->input('field');
];
}
}
This to me should work but according to my experience at the moment doesn't. I have tried to separate the rules by checking the incoming request method and assign rules based on whether the request is an update or create.
Shouldn't what I have suffice for this requirement? What would be the best way of re-using my FormRequest but making sure that I am able to validate uniqueness of as many table fields as I want regardless of their data types because I am sensing that perhaps this is related to the fact that Laravel seems to be doing an aggregate on the field being validated and if it is not an integer for example it will keep on displaying the error message.
Another possible way of solving this is if I implement my own validation method for the fields I am interested to validate. How would I go about doing this?

Answer 1

This rule works only if the primary key of "table_name" is "id" but if it is different then you have to write it as the fourth parameter to unique rule as follows:
<?php
class MyFormRequest extends Request{
public function rules(){
return [
'field' => 'required|unique:table_name:field,' . $this->input('field').','.'primary_key_field';
];
}
}
hope it help you !!!

Answer 2

You need to tell the validator which rows to exclude from duplicate search.
If your primary key is id, you need to pass its value:
'field' => 'required|unique:table_name,field,' . $this->input('id')
Your code has also some other errors:
'field' => 'required|unique:table_name:field,' . $this->input('field');
^ ^

Answer 3

The rule "unique" needs aditional arguments when updating. Those aditional arguments will be responsible for ignore the actual registry you're working on. If not applied, this rule will always invalidate, since the registry always will be found on database.
Your thirdy argument should be the ID you want to ignore. (you're passing a value...)
*Another thing: I picked up a misstype from your rule. Check below the right sintax with new arguments.
'field' => 'required|unique:table_name,field,'.$this->input('id')'
PS: if your id column from your table has a different name than "id", you need to specify this column name as the fourth parameter.
'field' => 'required|unique:table_name,field,'.$this->input('id').',column_name'