Specified key was too long; max key length is 1000 bytes

Question

importimg Joomla 1.5 database via mySQL dump but it gives error "1071 - Specified key was too long; max key length is 1000 bytes"

the culrpit sql statement is:

    CREATE TABLE  `jos_core_acl_aro` (

 `id` INT( 11 ) NOT NULL AUTO_INCREMENT ,
 `section_value` VARCHAR( 240 ) NOT NULL DEFAULT  '0',
 `value` VARCHAR( 240 ) NOT NULL ,
 `order_value` INT( 11 ) NOT NULL DEFAULT  '0',
 `name` VARCHAR( 255 ) NOT NULL ,
 `hidden` INT( 11 ) NOT NULL DEFAULT  '0',
  PRIMARY KEY (  `id` ) ,
  UNIQUE KEY (  `section_value` ,  `value` ) ,
  KEY  `jos_gacl_hidden_aro` (  `hidden` )
  ) ENGINE = MYISAM DEFAULT CHARSET = utf8 AUTO_INCREMENT =11;

MySQL said:

   #1071 - Specified key was too long; max key length is 1000 bytes

The source & destination database is UTF8. I still don't know why this error occurs :(

Answer 1

mysql stores utf8 encoded chars as 3 bytes

your key

UNIQUE KEY (  `section_value` ,  `value` ) ,

has a size of (240 + 240) * 3 bytes, which is greater then 1000 limit