OptionaldefaultOptional default value or expression metadata for the new column.
Physical SQL name of the new column.
Whether the new column permits SQL NULL.
OptionalonOptional ON DELETE action for the reference.
OptionalonOptional ON UPDATE action for the reference.
OptionalreferencesOptional referenced table/column for a new foreign key.
SQL type to create, including any declared length/precision.
A column to add in a migration.