Why should i use/not-use a nullable field Laravel - MySQL

5
votes

I have a Address table in my mySQL database with some fields.

On my form i ask a user to input values for these fields. But the street field is not required . So when my form gets submitted my Column Street is just empty in my database. This works fine and gives no errors without setting the column to accept NULL .

So my question is :

What is the benefit of setting the Street column to nullable?

Example migration (Laravel) without nullable: 

$table->string('street');

Example Migration with nullable

$table->string('street')->nullable();

Both work fine .

1
phpmysqllaravel
In your case, it probably doesn't really matter. In some other application, an empty string may not be the same thing as the absence of a string, so null serves a purpose there. I generally make fields that could be left out nullable as a best practice, but it's not something you have to do. – Joel Hinz
can you give an example where it will matter? – Christophvh
Unless you know you need the difference, it is unlikely to matter. :) – Joel Hinz
Ok, so basically the answer is to always use nullable because it will always work as intended? You can post that as an answer so i will accept it :) – Christophvh
In this case I don't think it matters but nullable can be useful for foreign key columns. Let's say you have a user_id foreign key on your address table and for some reason you have an address you need to store which doesn't belong to a user, you'd be able to set that user_id column to null and it should still work without violating the foreign key constraints where an empty space would. – user1669496

1 Answers

4
votes

It is just a good practice to use explicit instead of implicit where it's possible. So I'd go with nullable and is_null() checking for null.

With this approach you get less bugs, more readable code etc.