Error in the installation

i have this error when i try to creat an admin account

Error while trying to create admin user: An exception occurred while executing ‘CREATE TABLE oc_migrations (app VARCHAR(255) NOT NULL, version VARCHAR(255) NOT NULL, PRIMARY KEY(app, version)) DEFAULT CHARACTER SET UTF8 COLLATE utf8_bin ENGINE = InnoDB’: SQLSTATE[42000]: Syntax error or access violation: 1071 Specified key was too long; max key length is 1000 bytes

help me plss