module Onyx::SQL::Converters::SQLite3::UUIDBlob

Overview

Converts between the SQLite3 BLOB type and Crystal's UUID. See Field to read about of how to apply converters.

Comparison of Converters::SQLite3::UUIDBlob and Converters::SQLite3::UUIDText:

|                       | UUIDBlob | UUIDText |
| --------------------- | -------- | -------- |
| Bytes needed to store | 16       | ~32      |
| Comparable            | No       | Yes      |
| Can store array       | No       | Yes      |

When you use BLOB type for storing uuids, you cannot compare them with WHERE uuid = ? (making it useless as primary keys) and cannot store an array of uuids in a single column, but it occupies less bytes.

CREATE TABLE users (
  uuid  BLOB
);

require "onyx-sql/converters/sqlite3/uuid_blob"

class User
  include Onyx::SQL::Model

  schema do
    type uuid : UUID = UUID.random, converter: SQLite3::UUIDBlob
  end
end

Defined in:

onyx-sql/converters/sqlite3/uuid_blob.cr

Class Method Summary

• .from_rs(rs) : UUID?
• .from_rs_array(rs) : ::Array(UUID)?
• .to_db(value : UUID) : DB::Any
• .to_db(values : Enumerable(UUID)) : DB::Any

Class Method Detail