pub struct CreateDomain {
    pub name: ObjectName,
    pub data_type: DataType,
    pub collation: Option<Ident>,
    pub default: Option<Expr>,
    pub constraints: Vec<TableConstraint>,
}

CREATE DOMAIN name [ AS ] data_type
        [ COLLATE collation ]
        [ DEFAULT expression ]
        [ domain_constraint [ ... ] ]

    where domain_constraint is:

    [ CONSTRAINT constraint_name ]
    { NOT NULL | NULL | CHECK (expression) }

The name of the domain to be created.

The data type of the domain.

The collation of the domain.

The default value of the domain.

The constraints of the domain.