I wanted to create a session table with a unique index, but when the index was created, I encountered with this error with key limitation. Can you help me to create this table with these two indexes?

migration file

  def change
    create_table :sessions do |t|
      t.string :session_id, :null => false
      t.text :data
      t.timestamps
    end

    add_index :sessions, :session_id, :unique => true
    add_index :sessions, :updated_at
  end

error message

== 20240814053256 AddSessionsTable: migrating =================================
-- create_table(:sessions)
   -> 0.1219s
-- add_index(:sessions, :session_id, {:unique=>true})
rails aborted!
StandardError: An error has occurred, all later migrations canceled:

Mysql2::Error: Specified key was too long; max key length is 767 bytes: CREATE UNIQUE INDEX `index_sessions_on_session_id`  ON `sessions` (`session_id`) 
/home/antonivanov/projects/pay/db/migrate/20240814053256_add_sessions_table.rb:9:in `change'
/home/antonivanov/projects/pay/bin/rails:9:in `require'
/home/antonivanov/projects/pay/bin/rails:9:in `<top (required)>'
/home/antonivanov/projects/pay/bin/spring:15:in `<top (required)>'
bin/rails:3:in `load'
bin/rails:3:in `<main>'

Caused by:
ActiveRecord::StatementInvalid: Mysql2::Error: Specified key was too long; max key length is 767 bytes: CREATE UNIQUE INDEX `index_sessions_on_session_id`  ON `sessions` (`session_id`) 
/home/antonivanov/projects/pay/db/migrate/20240814053256_add_sessions_table.rb:9:in `change'
/home/antonivanov/projects/pay/bin/rails:9:in `require'
/home/antonivanov/projects/pay/bin/rails:9:in `<top (required)>'
/home/antonivanov/projects/pay/bin/spring:15:in `<top (required)>'
bin/rails:3:in `load'
bin/rails:3:in `<main>'

Caused by:
Mysql2::Error: Specified key was too long; max key length is 767 bytes
/home/antonivanov/projects/pay/db/migrate/20240814053256_add_sessions_table.rb:9:in `change'
/home/antonivanov/projects/pay/bin/rails:9:in `require'
/home/antonivanov/projects/pay/bin/rails:9:in `<top (required)>'
/home/antonivanov/projects/pay/bin/spring:15:in `<top (required)>'
bin/rails:3:in `load'
bin/rails:3:in `<main>'
Tasks: TOP => db:migrate
(See full trace by running task with --trace)

Additional info

• mysql-server: Version: 8.0.39-0ubuntu0.20.04.1
• rails version: 5.1.4
• ruby version: 2.4.2