ERROR 1100 (HY000) at line 11084: Table 'search_index' was not locked with LOCK TABLES I'm trying to import a mysqldump backup of a drupal database taken from a server running MySQL 5.0 (which will be upgraded to 5.5) onto my local machine running MySQL 5.5.23. The import fails with the below error:

ERROR 1100 (HY000) at line 11084: Table 'search_index' was not locked with LOCK TABLES


When I open up the backup at line 11084 here is what I get:

LOCK TABLES `sessions` WRITE;
/*!40000 ALTER TABLE `sessions` DISABLE KEYS */;
INSERT INTO `sessions` VALUES ...
-- MySQL dump 10.11
--
-- Host: localhost    Database: drupal
-- ------------------------------------------------------
-- Server version       5.0.77-log

/*!40101 SET @OLD_CHARACTER_SET_CLIENT=@@CHARACTER_SET_CLIENT */;
/*!40101 SET @OLD_CHARACTER_SET_RESULTS=@@CHARACTER_SET_RESULTS */;
/*!40101 SET @OLD_COLLATION_CONNECTION=@@COLLATION_CONNECTION */;
/*!40101 SET NAMES utf8 */;
/*!40103 SET @OLD_TIME_ZONE=@@TIME_ZONE */;
/*!40103 SET TIME_ZONE='+00:00' */;
/*!40014 SET @OLD_UNIQUE_CHECKS=@@UNIQUE_CHECKS, UNIQUE_CHECKS=0 */;
/*!40014 SET @OLD_FOREIGN_KEY_CHECKS=@@FOREIGN_KEY_CHECKS, FOREIGN_KEY_CHECKS=0 */;
/*!40101 SET @OLD_SQL_MODE=@@SQL_MODE, SQL_MODE='NO_AUTO_VALUE_ON_ZERO' */;
/*!40111 SET @OLD_SQL_NOTES=@@SQL_NOTES, SQL_NOTES=0 */;

--
-- Table structure for table `search_index`
--

DROP TABLE IF EXISTS `search_index`;        &lt;=== LINE 11084
SET @saved_cs_client     = @@character_set_client;
SET character_set_client = utf8;
CREATE TABLE `search_index` (
  `word` varchar(50) NOT NULL default '',
  `sid` int(10) unsigned NOT NULL default '0',
  `type` varchar(16) default NULL,
  `score` float default NULL,
  UNIQUE KEY `word_sid_type` (`word`,`sid`,`type`),
  KEY `sid_type` (`sid`,`type`),
  KEY `word` (`word`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8;
SET character_set_client = @saved_cs_client;


I checked the other statements and normally INSERT statements are followed by UNLOCK TABLES;. Accordingly if I make the below modifications to the mysqldump file the problem is fixed:

INSERT INTO `sessions` VALUES ...
UNLOCK TABLES;                   &lt;=== ADDED LINE
-- MySQL dump 10.11
[...]
DROP TABLE IF EXISTS `search_index`;


I don't know what's wrong there but the whole comment block starting with -- MySQL dump 10.11 is the same as the one at the beginning of the mysqldump file, and it looks like mysqldump started a new dump while writing the INSERT INTO sessions statements which were not closed properly with UNLOCK TABLES;.

Does someone have any idea as to what's going on here?
My initial guess would be that when the mysqldump file was being created, the option single-transaction was not used.

According to MySQL Documentation on single-transaction


  The --single-transaction option and the --lock-tables option are mutually exclusive because LOCK TABLES causes any pending transactions to be committed implicitly. 


The fact that you embedded UNLOCK TABLES; into the dump manually shows that neither option was called when the mysqldump was first created. Thus, upon reload, this error reared its ugly head.