text: SELECT '00000000-0000-01f8-9cb8-cb1b82fb3900' AS str, toUUID(str);
  SELECT toFixedString('00000000-0000-02f8-9cb8-cb1b82fb3900', 36) AS str, toUUID(str);
  
  SELECT '00000000-0000-03f8-9cb8-cb1b82fb3900' AS str, CAST(str, 'UUID');
  SELECT toFixedString('00000000-0000-04f8-9cb8-cb1b82fb3900', 36) AS str, CAST(str, 'UUID');
  
  DROP TABLE IF EXISTS uuid;
  CREATE TABLE IF NOT EXISTS uuid
  (
      created_at DateTime,
      id0 String,
      id1 FixedString(36)
  )
  ENGINE = MergeTree
  PARTITION BY toDate(created_at)
  ORDER BY (created_at);
  
  INSERT INTO uuid VALUES ('2018-01-01 01:02:03', '00000000-0000-05f8-9cb8-cb1b82fb3900', '00000000-0000-06f8-9cb8-cb1b82fb3900');
  
  ALTER TABLE uuid MODIFY COLUMN id0 UUID;
  ALTER TABLE uuid MODIFY COLUMN id1 UUID;
  
  SELECT id0, id1 FROM uuid;
  SELECT toTypeName(id0), toTypeName(id1) FROM uuid;
  
  DROP TABLE uuid;
  
  -- with UUID in key
  
  CREATE TABLE IF NOT EXISTS uuid
  (
      created_at DateTime,
      id0 String,
      id1 FixedString(36)
  )
  ENGINE = MergeTree
  PARTITION BY toDate(created_at)
  ORDER BY (created_at, id0, id1);
  
  SET send_logs_level = 'fatal';
  
  ALTER TABLE uuid MODIFY COLUMN id0 UUID; -- { serverError 524 }
  ALTER TABLE uuid MODIFY COLUMN id1 UUID; -- { serverError 524 }
  
  DROP TABLE uuid;
  