MariaDB backend (content: VARCHAR vs MEDIUMTEXT)

[vecinohk]

Hello, the standard MariaDB backend uses VARCHAR(64000) content, which is not much. If we use MEDIUMTEXT instead of VARCHAR, will that be okay for pdns?

Why am I asking? We use createReverse6 and expect that exceptions will increase over time, so we may soon reach a point where this is no longer sufficient.

CREATE TABLE records (
  id                    BIGINT AUTO_INCREMENT,
  domain_id             INT DEFAULT NULL,
  name                  VARCHAR(255) DEFAULT NULL,
  type                  VARCHAR(10) DEFAULT NULL,
  content               VARCHAR(64000) DEFAULT NULL,
  ttl                   INT DEFAULT NULL,
  prio                  INT DEFAULT NULL,
  disabled              TINYINT(1) DEFAULT 0,
  ordername             VARCHAR(255) BINARY DEFAULT NULL,
  auth                  TINYINT(1) DEFAULT 1,
  PRIMARY KEY (id)
) Engine=InnoDB CHARACTER SET 'latin1';

MariaDB - MEDIUMTEXT doc

[Habbie]

We will likely make this change in the future - see #11895

However, I'm not sure this will help for your createReverse6 exception table - there might be similar 64k limits hiding in other places. It might make more sense to store your exceptions in a file and load it when needed. If you use enable-lua-records=shared, Lua state sticks around between calls and you can keep the table in memory with some effort.

[vecinohk]

Yes, thank you for the tip - the problem with loading from a file is that I can't transfer the records via AXFR as I do now.

I think my concerns are unnecessary. The current limit VARCHAR(64000) is quite sufficient for us at the moment.