Laravel make merged created_at and updated_at timestamps

In a model I have created custom timestamps:

const CREATED_AT = 'fil_ts'; const UPDATED_AT = 'fil_ts'; 

Basically the idea is that CREATED_AT timestamp will get updated whenever record is changed (in other words: I would have just one timestamp which acts as created and updated timestamp).

How do I make these custom timestamps appear in the database's table trough migrations? Do I need to create them in the migration file when I create the table?

1. Do i need to define custom timestamps in migration like this

$table->timestamp('fil_ts'); $table->timestamp('fil_ts'); 

2. or like this

$table->timestamps(); 

So far neither of these methods worked. With the first method I get an error that I can't have same named variables (which is logical, but I don't know other way how to make SINGLE timestamp act as CREATED_AT and UPDATED_AT).

If I use the second method it just creates default timestamps.

My end goal: a single custom timestamp that acts like created_at and updated_at. First it gets creation timestamp and then it keeps updated.

Update

Even if the custom timestamps names are different I still get error when I run php artisan migrate:

Timestamps in the model:

 const CREATED_AT = 'file_created'; const UPDATED_AT = 'file_updated'; 

Timestamps in the migration:

 $table->timestamp('file_created'); $table->timestamp('file_updated'); 

Doctrine\DBAL\Driver\PDOException::("SQLSTATE[42000]: Syntax error or access violation: 1067 Invalid default value for 'file_updated'")

Solution

Code in the model: Need to disable default timestamps

public $timestamps = false; const CREATED_AT = 'fil_ts'; const UPDATED_AT = 'fil_ts'; 

Code in the migration

$table->timestamp('fil_ts');