change_column_null change_column_comment (must supply a :from and :to option) change_table_comment (must supply a :from and :to option) create_enum create_join_table create_table disable_extension drop_enum (must supply a list of values) drop_join_table drop_table (must supply a block) enable

Sets or removes a NOT NULL constraint on a column. The null flag indicates whether the value can be NULL . For example allows them to be NULL (drops the constraint). The method accepts an optional fourth argument to replace existing NULLs with some other value. Use that one when enabling

Sets or removes a NOT NULL constraint on a column . See {connection.change_column_null}[rdoc-ref:SchemaStatements#change_column_null]