link type to a record ▸ DOUBLE and INT64 are numbers ▸ BYTES is Base64 encoded array of bytes ▸ TIMESTAMP is for dates and times in seconds ▸ STRING is string obviously ▸ ASSETID is for assets. Assets are stored separately to the database itself. ▸ REFERENCE_LIST ▸ DOUBLE_LIST ▸ INT64_LIST ▸ BYTES_LIST ▸ TIMESTAMP_LIST ▸ STRING_LIST ▸ ASSETID_LIST