MariaDB 10.6

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create table if not exists connector
(
    id char(36) not null,
    # other fields omitted
    primary key (id)
) DEFAULT CHARACTER SET 'utf8mb4'
  COLLATE 'utf8mb4_unicode_520_ci';
CREATE TABLE IF NOT EXISTS connector_preset
(
    id CHAR(36) NOT NULL,
    # other fields omitted

    PRIMARY KEY (id)
)DEFAULT CHARACTER SET 'utf8mb4'
  COLLATE 'utf8mb4_unicode_520_ci';
ALTER IGNORE TABLE `connector`
    # `connector_preset`.`id`
    ADD COLUMN IF NOT EXISTS `preset_id` CHAR(36),
    ADD CONSTRAINT `fk_connector_preset_id` FOREIGN KEY (`preset_id`) REFERENCES `connector_preset` (`id`);

Records: 0  Duplicates: 0  Warnings: 0


show create table connector;
show create table connector_preset;


Table
Create Table


connector
CREATE TABLE `connector` (
  `id` char(36) COLLATE utf8mb4_unicode_520_ci NOT NULL,
  `preset_id` char(36) COLLATE utf8mb4_unicode_520_ci DEFAULT NULL,
  PRIMARY KEY (`id`),
  KEY `fk_connector_preset_id` (`preset_id`),
  CONSTRAINT `fk_connector_preset_id` FOREIGN KEY (`preset_id`) REFERENCES `connector_preset` (`id`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_unicode_520_ci




Table
Create Table


connector_preset
CREATE TABLE `connector_preset` (
  `id` char(36) COLLATE utf8mb4_unicode_520_ci NOT NULL,
  PRIMARY KEY (`id`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_unicode_520_ci