What does the MySQL 5.6 error “InnoDB presently supports one FULLTEXT index creation at a time. Try LOCK=SHARED” mean?

Question

In MySQL 5.6.22 (specifically running on Amazon RDS) I once had a fulltext index on a table. I have since dropped that index in favor of using sphinxsearch. There are no more fulltext indexes on any of the tables on the database.

When I try to now perform an online DDL such as adding a tinyint column to a table with LOCK=NONE I get this error:

InnoDB presently supports one FULLTEXT index creation at a time. Try LOCK=SHARED.

But, there are no fulltext indexes anywhere. I've even tried creating a read-replica in Amazon in hopes that the rebuilding of the database would fix that and I get the same error there.

Am I missing something obvious?

SHOW CREATE TABLE:

CREATE TABLE `pages` (
  `ID` char(64) CHARACTER SET latin1 NOT NULL,
  `auto_id` bigint(20) unsigned NOT NULL AUTO_INCREMENT,
  `siteID` bigint(20) unsigned NOT NULL,
  `recordingID` char(64) DEFAULT NULL,
  `dateCreated` datetime DEFAULT NULL,
  `ip` char(46) CHARACTER SET latin1 DEFAULT NULL,
  `referrer` text CHARACTER SET latin1,
  `referrer_client` char(50) DEFAULT NULL,
  `referrer_from` char(255) DEFAULT NULL,
  `referrer_type` char(50) DEFAULT NULL,
  `referrer_network` char(50) DEFAULT NULL,
  `referrer_link` char(255) DEFAULT NULL,
  `campaign_source` char(50) DEFAULT NULL,
  `campaign_medium` char(32) DEFAULT NULL,
  `campaign_campaign` char(75) DEFAULT NULL,
  `url` char(255) CHARACTER SET latin1 DEFAULT NULL,
  `keywords` char(100) CHARACTER SET latin1 DEFAULT NULL,
  `source` char(128) CHARACTER SET latin1 DEFAULT NULL,
  `os` char(30) CHARACTER SET latin1 DEFAULT NULL,
  `browser` char(30) CHARACTER SET latin1 DEFAULT NULL,
  `user_agent` char(255) CHARACTER SET latin1 DEFAULT NULL,
  `agentFamily` char(50) DEFAULT NULL,
  `is_phone` tinyint(1) DEFAULT '0',
  `is_tablet` tinyint(1) DEFAULT '0',
  `is_desktop` tinyint(1) DEFAULT '0',
  `tags` char(255) CHARACTER SET latin1 DEFAULT NULL,
  `device` char(65) DEFAULT NULL,
  `last_event_time` datetime DEFAULT NULL,
  `view_width` int(11) DEFAULT NULL,
  `view_height` int(11) DEFAULT NULL,
  `browser_width` int(11) DEFAULT NULL,
  `browser_height` int(11) DEFAULT NULL,
  `optimizely_experiments` char(255) CHARACTER SET latin1 DEFAULT NULL,
  `optimizely_variations` char(255) CHARACTER SET latin1 DEFAULT NULL,
  `is_paid` tinyint(1) DEFAULT '0',
  `typed` tinyint(1) DEFAULT '0',
  `organization` char(255) CHARACTER SET latin1 DEFAULT NULL,
  `country` char(75) CHARACTER SET latin1 DEFAULT NULL,
  `city` char(128) CHARACTER SET latin1 DEFAULT NULL,
  `region` char(10) DEFAULT NULL,
  `regionName` char(64) DEFAULT NULL,
  `country_code2` char(2) CHARACTER SET latin1 DEFAULT NULL,
  `postal` char(32) CHARACTER SET latin1 DEFAULT NULL,
  `latitude` char(30) DEFAULT NULL,
  `longitude` char(30) DEFAULT NULL,
  `custom_data` text CHARACTER SET latin1,
  `notes` text CHARACTER SET latin1,
  `title` char(255) DEFAULT NULL,
  `has_dom_tree` tinyint(1) DEFAULT '0',
  `time` int(11) DEFAULT NULL,
  PRIMARY KEY (`auto_id`),
  UNIQUE KEY `pageid` (`ID`),
  KEY `siteID` (`siteID`),
  KEY `dateCreated` (`dateCreated`),
  KEY `recordingID` (`recordingID`),
  KEY `siteID_url` (`siteID`,`url`)
) ENGINE=InnoDB AUTO_INCREMENT=90042803 DEFAULT CHARSET=utf8

Simple Alter

ALTER TABLE `pages`   
  ADD COLUMN `is_ppc` TINYINT(1) , LOCK=NONE

Error

Error Code: 1846
LOCK=NONE is not supported. Reason: InnoDB presently supports one FULLTEXT index creation at a time. Try LOCK=SHARED.

Answer 1

There is no fix. The two workarounds include:

1. rebuild the table, or
2. LOCK = SHARED

-- neither of which meet the criterion of "no locks".

I would recommend filing a report at the MySQL bug tracker. In the meantime, here is a test case that fails for me too:

drop table IF EXISTS so28666643a;
CREATE TABLE so28666643a (ai INT AUTO_INCREMENT PRIMARY KEY,
    txt TEXT NOT NULL ) ENGINE=InnoDB;
ALTER TABLE so28666643a ADD COLUMN x TINYINT, LOCK=NONE;  -- works OK

drop table so28666643a;
CREATE TABLE so28666643a (ai INT AUTO_INCREMENT PRIMARY KEY,
    txt TEXT NOT NULL ) ENGINE=InnoDB; -- same
ALTER TABLE so28666643a ADD FULLTEXT(txt);
ALTER TABLE so28666643a DROP INDEX txt;
ALTER TABLE so28666643a ADD COLUMN x TINYINT, LOCK=NONE;  -- fails with strange message:

ERROR 1846 (0A000): LOCK=NONE is not supported.
Reason: InnoDB presently supports one FULLTEXT index creation at a time.
Try LOCK=SHARED.

Edit: thanks for the bug report.

Answer 2

Found better workaround (solution),

I changed the table engine from InnoDB to MyISAM i.e.

ALTER TABLE `tablename` ENGINE='MyISAM';

and then I ran alter table to add fulltext column index:

ALTER TABLE `tablename` ADD FULLTEXT `asset_number` (`asset_number`);

After that, I changed back the table engine to InnoDB.

ALTER TABLE `tablename` ENGINE='InnoDB';