text: CREATE TABLE IF NOT EXISTS `DOI` (
  	`ID`              bigint(20)                           NOT NULL,
  	`ETAG`            char(36)                             NOT NULL,
  	`DOI_STATUS`      ENUM('IN_PROCESS', 'CREATED', 'READY', 'ERROR') NOT NULL,
  	`OBJECT_ID`       bigint(20)                           NOT NULL,
  	`OBJECT_TYPE`     ENUM('ENTITY', 'EVALUATION')         NOT NULL,
  	`OBJECT_VERSION`  bigint(20)                           NOT NULL,
  	`CREATED_BY`      bigint(20)                           NOT NULL,
  	`CREATED_ON`      TIMESTAMP                            NOT NULL,
    `UPDATED_BY`      bigint(20)                           NOT NULL,
  	`UPDATED_ON`      TIMESTAMP                            NOT NULL,
  	PRIMARY KEY (`ID`),
  	UNIQUE INDEX (OBJECT_ID, OBJECT_TYPE, OBJECT_VERSION)
  )
  