For at matche mod en lang varchar- eller klatkolonne skal du angive indekslængden:
create table SOURCES (
SOURCES_PK int not null AUTO_INCREMENT primary key,
SOURCE_URL text not null unique,
DESCRIPTION varchar(255),
INDEX source_url (source_url(100)) );
// Key length ----------------^^^
Til MyISAM
For InnODB
Se:http://dev.mysql.com/doc /refman/5.5/da/create-table.html