create table fields (
  type text references scalar_types not null,
  is_array boolean not null,
  fields ,
  label text,
  description text
);
comment on table fields is '
  Single field of a topic schema. A field can be used for projecting, filtering and sorting in reports.
';

comment on column fields.type is '
  The (scalar) type of the field. Fields can only be primitive types.
';
comment on column fields.is_array is '
  Setting this to `true` means the field is an array of given type.
';
comment on column fields.fields is '
  Nested fields for type `object`. When defining fields but not having set the type to `object`, the fields will be ignored. When setting the type to `object`, the fields need to be defined.
';
comment on column fields.label is '
  A human-readable label for the field.
';
comment on column fields.description is '
  A human-readable description of the field.
';