Unsupported type Nullable(Date) when trying to load range_hash MySQL dictionary

[Zer0Divis0r]

Upgraded to 8.12, and my external range_hash dictionary that loads data from MYSQL stopped working.
Error message is: Unsupported type Nullable(Date).

Downgraded to 8.6 and it works fine. Because did not have time to dig further could not try any other versions, just semi-randomly selected 18.6 after going over some change logs.

[EvgenyVinogradov]

Same problem with ODBC(Postgres) dictionaries

[den-crane]

Probably this ability (nullable types for range_min range_max at backend) was removed with #2093 (it was released in 18.12.17)

I suggest to try workaround and cast to notnull type using view (mysql/pg), though it will break index access.

[Zer0Divis0r]

The schema of my dictionary follows. Which of the fields is nullable type? How can they be done not nullable...?

CREATE TABLE `sampling_history` (
  `id` int(10) UNSIGNED NOT NULL,
  `websiteId` int(11) UNSIGNED NOT NULL,
  `dateFrom` date NOT NULL DEFAULT '2017-06-01',
  `dateTill` date NOT NULL DEFAULT '2050-10-30',
  `probability` smallint(3) UNSIGNED NOT NULL DEFAULT '0',
) ENGINE=InnoDB DEFAULT CHARSET=latin1;

[den-crane]

@Enmk

check this, range_hashed does not work with any type

Received exception from server (version 18.14.6):

Code: 50. DB::Exception: Received from localhost:9000, ::1. DB::Exception: Unsupported type Nullable(UInt64).

Code: 50. DB::Exception: Received from localhost:9000, ::1. DB::Exception: Unsupported type Nullable(Date).

Seems the problem with mysql and at least postgressql. Http works fine.

[alexey-milovidov]

Broken after #3123
Steps to reproduce: https://gist.github.com/alexey-milovidov/c31b37f56114b822c7fdcf21d8557c9d

[alexey-milovidov]

Fixed in master.