Difference between IsRequired(false) and omitting using it when adding properties (Entity Framework)

Question

So I'm wondering about the difference between setting IsRequired() to false and simply not using it when setting up a property for a database table. Is the default behaviour when not using IsRequired() to allow the property to be nullable?

I don't have trial and error examples, just noticed on a project that whether it's false or not null, the table in the database displays the property as nullable either way. So is there a difference between not using IsRequired() at all or using it and setting it to false?

Answer 1

It's safe to assume that if you don't explictly declare a property as not-required, or you do so explicitly but set it to false, then you will get the same result.

I've had a quick dig around the EF Core source code, and the nearest I can come up with a definitive answer is the constructor for ForeignKey :

public ForeignKey(
    IReadOnlyList<Property> dependentProperties,
    Key principalKey,
    EntityType dependentEntityType,
    EntityType principalEntityType,
    ConfigurationSource configurationSource)
{
    ...
    _isRequired = DefaultIsRequired;

and

private bool DefaultIsRequired
    => !Properties.Any(p => p.IsNullable);