ALTER TABLE /*_*/job
    ADD COLUMN job_random integer unsigned NOT NULL default 0,
    ADD COLUMN job_token varbinary(32) NOT NULL default '',
    ADD COLUMN job_token_timestamp varbinary(14) NULL default NULL,
    ADD COLUMN job_sha1 varbinary(32) NOT NULL default '';

CREATE INDEX /*i*/job_sha1 ON /*_*/job (job_sha1);
CREATE INDEX /*i*/job_cmd_token ON /*_*/job (job_cmd,job_token,job_random);