SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '650921beda03bfca8326df65030d4959f16f4f93d0375b448735b2dab24a6562' 
  AND token = 'OvVILq4GZw7YxBTMefWit62Wq8MCaNG8tswlO3fpB1E=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}